We are running a monthly $100 small community contest on vBulletin.org. Get enough nominations to make it to the polls (top 5), and then get enough votes to win the contest. There are no restrictions on promotion such as rallying, just make sure you qualify. Nominations start on the first of the month and end on the 15th. Voting runs from the 16th to the 28th. April 2013's nominations start early (March 23rd) and end on the standard closing day.

More here: http://www.vbulletin.org/forum/showthread.php?t=296447