Live Casino Hero. You can opt in at the link Steve shared.
Simple premise. Wager on live casino every day with everyone else participating. Miss a day and you drop out. The first edition featured 92 days of consecutive wagering, and then 1 BTC was shared with everyone still left alive. This time, if I read the rules, seems to suggest only 1 player left standing... should be all kinds of epic.
Edit: 31 Dec is last day. That'll be 120 days give or take.
This is certainly a cult event, but perhaps I'll skip it (although it's so tempting). The thing is, in order to qualify for the prize, you need to have at least 0.5 bitcoin on your balance, not to mention the fact that I saw that DS_ expressed a desire to participate. So I won't have any chance of winning.