I was just wondering about the Rupee system you've added. I was looking at the Sprite competitions, and how people were talking about winning rupees...
Well, what if you could use your admin/competition moderator to subtract the rupees from their account, and then add them together as a bet? ...Or just give them the total.
Whoever wins would obtain the rupees. It could be used for a couple of things.
Of course, you'd have to have proof that they accepted the bet, something like a post being "I accept the competition..."
Just an idea.