My choice: Find friends and do a team costume, i.e. lemmings. Mimic being blown up. Build stairs. Put arms out and shake head back and forth.

ntn

Lemmings are awesome. Do that!

quince

cooler, but more effort and less effect if you aren't all together

aletta

only do a group if it's really good.

lakmiseiru

Team costumes are so much fun!

kevinr

Lemmings!

jesse, paigep, geoff, seph, trs, kyrandil, Ian, beppu, nelhage, Alex