Messing with a friends computer

[PapaSimmz]

So my roommate left his computer unlocked and me and him are always going back and forth just messing with each others computer. I have ran out of ideas, what do you guys have? Keyloggers? anything i can plant that can let me access it later?

[Guest]

How bout you don't be a jerk, and install updates as well as remove malware?

[Imabigmac]

just get that easy program file that opens and closes the CD drive. 

[Kyuubixchidori]

dude keyloggers and accessing later is to much. dont be a dick. being funny is one thing, but you directly asked for a keylogger. not cool ihmo

[soaringchicken]

Install a remote control program and F with it later on and he'll freak. 

EDIT: and this 

[Sam Z Man]

Don't take a joke to far, you only will make yourself become a asshole.

[STRMfrmXMN]

So my roommate left his computer unlocked and me and him are always going back and forth just messing with each others computer. I have ran out of ideas, what do you guys have? Keyloggers? anything i can plant that can let me access it later?

In the latest pages of the Experiences With Non techies thread you can find some hilarious (harmless) batch files that can be funny and solved with a simple restart. 

[SirSquid]

Install a remote control program and F with it later on and he'll freak. 

EDIT: and this 

You beat me to it.

[Oshino Shinobu]

You could create a simple program that presses random keys and makes mouse movements. I think Jerry (Barnacules) did a tutorial on it for one of his Codegasm videos.