The most epic BTC wins for me so far have been from Bitlotto.com
May 2012 bet 112 btc, won jackpot of 387 btc
Aug 2012 bet 121 btc, won jackpot of 270 btc
What percentage of the jackpot was 'contributed' by you?
May 112/387 * 100 = 28.94%
Aug 121/270 * 100 = 44.82%
I was betting to show support & make a nice jackpot for everyone.