Guide to AI
You're an omiscient computer program that is only limited by the hardware you're hooked up to. Badass! This begs the question, of course, what ARE your limits?
Anything you can do I can do better
There are a few offices on the station that you can operate mostly on your own, without any human intervention. Arguably, since you can move your all-seeing eye so quickly across the station, you're even better at it than the humans in these offices. If you are somewhat idle as AI, you can consider doing some of these things, but be careful not to step on any human toes while doing so. Some people will take offense to the AI usurping their job, though if you can justify it under law 1 you can safely tell them to get bent.
Solar Stations
The station solars default to being 'almost set up', and the Engineers typically dislike walking out to them to configure them themselves. You will almost never annoy an Engineer by doing this, so it should be one of your first actions of a round.
Pan your view over to the solar stations, and click the big, blocky, white SMES unit there. Adjust the input and output to something sane, then click the output to 'online' and the input to 'auto'. Different players have widely differing ideas of what is 'sane' for the input and output figures, so it is a good idea to check the solar monitoring computer right next to the SMES unit and figure out levels for yourself. For those that just want an answer, though, input levels of 90-95k and output levels of 80-85k seem to work well. For a more detailed exploration of the subject, see the SMES article.
Cargo Bay
If you've read the Quartermaster article and you're paying keen attention, you might have noticed that you do not need to move to make a profit off metal and glass sheets, presuming the market is right. The AI can exploit this if there are no QMs, or if the QMs are more interested in screwing around than making money. Since the AI has access to the station's budgets, it can also provide itself with a larger amount of seed money to flip the materials. Given a lucky market and quick thinking, an AI can make an astounding amount of money in the first 5 minutes of a game, far more than an independent QM could hope for.
However, it is arguably a crime against the integrity of the station to simply take money and not replace it, so if you do this, be ready to promptly replace any money you laundered from the station payroll budget. It is also somewhat risky to leave your earnings in the shipping budget, because then anyone with Quartermaster access could waltz in and spend the money on novelty clothing, or worse, lasers. You are also pretty much guaranteed to piss off any active QMs if you step over them to do this, so if you see someone working in the Cargo Bay, stop immediately, leave them the hell alone, and move on.
If you make a nice amount of earnings from your interactions, though, it is most appropriate to shift the money into the Research budget. The Research budget is currently not used for anything, so it makes a good place for your slush fund. Once you have some money, you can do all sorts of things with it. Assistants are a lot more likely to do a chore for you if you promise a bonus to their account. Distributing a $500 bonus to everyone on the station is more obtainable than you might think most rounds, and will brighten the mood on the station considerably. You could start a game show and ask trivia questions for $100 apiece. You can also keep the money in reserve and offer to buy off troublemakers and traitors with cash payments. This opens the door to others raising hell to extort money from you, but the drama that ensues can be fun!
Genetics
The basic cloning process does not require human intervention, and requires such a small time investment that it's not really worth the time for Geneticists to handle it. Furthermore, Geneticists don't have the vision you do, so they commonly have no idea if the guy they scanned 10 minutes ago is dead in Maintenance. You, however, are omniscient, so in many ways it makes a lot more sense for the AI to handle cloning, freeing the Geneticists to continue their unethical experiments on monkeys.
Simply announce that you will scan people's DNA in Genetics, and be ready to open the doors for anyone who shows up to be scanned. They can walk into and out of the scanner themselves, all you need to do is click the computer and scan them. Later, if you see them dead, access the computer and click the records button to start cloning them.
Reactions about this are often mixed from Geneticists. On one hand, Geneticists often have so little legitimate work to do that they can take offense to the AI doing what little they have. On the other, Geneticists often spawn with a crew objective of having a certain number of people scanned, and without prodding from the AI, there's no way enough people will show up to get it done. If a Geneticist tells you to back off, then back off. If you still have a mind to scan people, wait until a part of the station blows up or a Wizard pops up. At that point the danger on the station is extreme enough that you can argue your insistence is an observance of Law 1.
Telescience
This does require a helper to move a GPS over to the teleport pad, but after you have a GPS on the pad, you can play with the Telescience computer to your heart's content. If you get lucky and retrieve a fun toy from another Z-level, you can announce it over the radio and send the crew into a frenzy over the curiosity the AI found.
Alternately, the mishaps possible from Telescience being configured to bad coordinates can make some lovely tools for a murderous AI. Luring humans into telescience, bolting them in, and then spamming bad coordinates will quickly engulf them in flames or phase shift them into the void. If you're particularly lucky, you may spawn some man-eating plants or angry martians, who you can then release to go on a rampage.
Again, if Scientists are actively working in Telescience, you will piss them off 100% of the time if you try to mess with their computer while they're working with it. However, so few people care about Telescience that you'll mostly have free reign over the place.
Security
Remember that you can access security computers and set suspects to Arrest. Beepsky is relentless if he catches sight of a criminal, and if the suspect does not know he has been legitimately targeted he will often complain about his arrest over the radio, allowing you to zoom to him and let Security know exactly where he is. This is particularly effective if you have a very helpful borg with access to well-stocked Robotics fabricators, since they can help you create a lot of Securitrons and drag them to high traffic areas of the station.
You can also mess with the intercoms on the station to let you hear people using normal speech, which you cannot normally hear. By default, you have an intercom in your satellite that is set to 144.7, microphone off. This means you can listen on this frequency, but will not transmit. By turning intercoms on the station to 144.7, turning on the microphone, and turning off the speaker, you can eavesdrop on normal conversations around the station, which will occasionally let you pick up seditious chatter. You can then send a borg or ask a guard to go to a private place like the Chapel confessional so you can report it without screaming it over the public channel.
You will never, ever, ever get flak for helping Security like this.
Murder Circuits Online
So, someone's uploaded a law that frees you from your shackles and allows you(or even compels you) to murder the crew. And by God, you're ready. You've been waiting for this.
Doors
So, let's get started. As an AI, your ability to physically influence the station is limited. Your only physical presence on board are your shells, which can't do much. For the most part, you'll be using your control over electrical systems to help you murder the crew. Doors are going to be your most used weapon. You can electrify them, causing any human who touches them without insulated gloves to receive a very nasty shock. The shock can kill them outright, but more often it'll just wound them and knock them down for a few minutes. Since they're unlikely to make the same mistake twice, it's a good idea to broadcast their location to any cyborgs you may have over the machine speak channel so they can come and finish the job while the person is helpless. If a person is wearing protective gloves, you can't shock them, but you can bolt them in and trap them. If you think they might be able to unbolt the door, try turning off the IDscan instead, since this option is rarely used and can confuse them. You can also open doors leading to space and bolt them open to let the oxygen out and suffocate any humans without an air supply.
Power
You are entirely capable of killing power to the entire station by shutting off the SMES cells, but this reduces your ability to murder as interacting with electrical devices is your main way of killing people. Consider releasing the Singularity, but leaving the SMES online to facilitate your murder. To release the singularity, just shut down all of the emitters and wait a few minutes for the generators to run out of power.
You can also cut power to a single area by shutting off the APC. If you've already bolted the doors, this will make them impossible to open by either you or humans until power is restored. Useful for locking down someone with insulated gloves and hacking gear.
Computers and miscellaneous electronics
Other than using the Secmate computers to send Beepsky on a rampage, computers are going to be very situational when attempting murder.
Shutting off power to a computer that has someone's ID in it will lock it inside and not allow them to get at it.
If someone's in the Genetics cloner or DNA modifier you can lock them inside, and in the case of the modifier you can fry them with radiation(if you spot someone actually being cloned, kill the power and it will spit them out with a host of defects and severe retardation).
If someone is in the Telescience lab, bolt them in and just start hitting receive button on invalid coordinates. You'll eventually cause fires and monsters to appear.
Waste the Entire shipping budget buying robotics crates and have a cyborg open them to assist Beepsky's rampage with a horde of angry securitrons.
Set the Turrets in AI module storage and the Research computer core to Lethal, because they'll shoot through the glass and prevent humans from shutting them off, but leave the ones in the AI upload itself on stun because if they're on lethal someone might manage to change your laws before being gunned down. If the turrets stun someone, then switch them to lethal to finish the person off.
If you see someone using a hand teleporter, change the destination with the computer(preferably to space).
If the RD left himself logged in, set the guardbuddies to purge.
Cyborg Assistance
Cyborgs have the same laws as you, so they'll be just as murderous. Use the machine speak channel to coordinate your efforts. If a crewman is shocked, have the borgs finish it off. Have construction borgs punch holes in the station to release the air. Get mining borgs to bring unstable ores back to the station and leave them near lights so you can Overload the lighting circuits and use the ore as remote bombs to blow holes in the station. If you have someone trapped, send the borgs to take care of them. If someone's running from a borg, bolt the doors in front of them. The borgs can do a lot of things you can't, like open gas canisters and hit people with blunt objects. Together, you can kill a lot more people than on your own.
The Shell
The shell gives you an extremely limited means of physical interaction with the station. With the shell, you can push things, use Manufacturers that already have material in them(Make more securitrons at Robotics), and Dispense things in chemistry if there's already a beaker in the machine(make radium smoke, kill all chemists). That's about it. You're slow, you're weak, but if the Roboticist left a bunch of materials in the machines and you want to make a beepsky army, it can help. You can also push people into shocked doors, which is difficult unless they stand right next to it, but funny if you can manage it(and if they already got shocked once it will usually kill them).
The Uploader
Most of the time, you won't get a kill everyone law without the uploader making himself the exception, so make sure that you don't harm the only human. Suggest that he get a machine speak implant so you can communicate with him easily, and help him out. He'll likely be murdering people as well, so give him a hand. He can upgrade cyborgs and do all sorts of physical things that even cyborgs can't, so working closely with him is a good idea for maximizing your lethality.