Here's something that bugs me:
People who use the company microwave, but then leave the door open and the clock still sitting at :09.
If you're gonna use it, please, close the freakin' door and reset the timer. And if cheese from your sub sandwich spills inside the microwave (or butter from the microwave popcorn or soup that boiled over), please clean that up as well. Your mom doesn't work here (and if she does, she probably has better things to do than to go around to all the microwaves and clean them and close their doors and reset their timers for you.. and this should be the case even if she is part of the cleaning crew).
This also goes for you Mr. or Mrs. Missed Putting The Paper Towel Into The Garbage Can But I'll Just Leave It On The Floor For The Maintenance People To Pick Up.