We had to do that one year.... my section decided to get all dadaist and duct-tape a bunch of forks and a cutout picture of a scuba diver to the door...
Dunno if that would work for you...but we got an award for "most interesting"...
Hawking - 80 Necromancer, AOC Mannannan server, TELoE
Also currently enjoying Left 4 Dead on XBL.
Hang a stuffed santa with a noose and duct tape his hand and feet together and some over his mouth. Tape a severed reindeer head next to him, using red streamer paper for blood. Merry fucking Xmas!
"There is at least as much need to curb the cruel greed and arrogance of part of the world of capital, to curb the cruel greed and violence of part of the world of labor, as to check a cruel and unhealthy militarism in international relationships." -Theodore Roosevelt