You've got to love when a poll option with a vote in it is counted as 0%.
I guess that I prefer "big" battles. The largest I've ever done was an epic five way battle, with a team with tons of vehicles in the middle, two groups of two allied teams on either side of the middle base, and at least 150 minifigs fighting. It took around 4-5 hours, one team leaving in the middle, a giant EMP device, a MKVI missile, Admiral Ackbar, a Psycho Jester, Four angry farmer hillbillies, and five Nova Swords to finish.
Sadly, there were no pics outside of some overviews (I could possibly use a flashdrive to steal those...) but most of what was in the middle is in this thread: http://www.brikwars.com/forums/viewtopic.php?t=4749
The next biggest is probably The Battle of BlurryPic Village: http://www.brikwars.com/forums/viewtopic.php?t=4919
I'm currently assembling terrain and factions for what should be another five way battle over Thanksgiving Break.