I recently discovered a cool fantasy site, Rotohog.com
In addition to some insightful fantasy information and analysis, Rotohog seems to have come up with a completely new game. It is unlike any fantasy experience I've ever seen before, using real-time market values for players that you can 'buy' and 'sell' to maximize the value of your team. Nuances of the game are explained more in depth at the Rotohog Blog.
If you're a hardcore fantasy addict, I strongly suggest you check it out.