Shorting out computers?

So, I'm quitting my job, and I absolutely hate my boss.  Any recommended ways to short out some of his goods while making it all look 'natural'?

To list, this includes a couple of PCs, a Laptop, and some other office machines like faxes and the like.

Water is always fun.

It's a little hard to make water look natural in an otherwise dry office space.

Depending on the intelligence of people who might be looking at the evidences... Mess with heatsinks and fans. Scrape thermal grease off heatsinks. Unplug fan power connectors. A graphite pencil can be used on the leads of most any chip to decrease resistance on that lead, potentially allowing too much voltage on that circuit, all that is needed is a dark line be made on the lead. Or do the opposite, reduce votages in BIOS below specs, so the machines will crash constantly whenever CPU useage goes above a certain point.

Take out the fuse on the cable? Alternatively make a vbscript that runs everytime your boss logged in and after say 3-4 month you left, make IE open gay porn site every 5 minute. Or plugging the floppy power upside down that usually melt the floppy connector.

>>2
They're more resistent to water than you'd think.

Get some cloth that creates static well, then touch the motherboard and periphals while you rub the cloth to create static and the power wire is connected(< this part increases chances of you fucking something up on atx) but system is turned off.