HedgeStreet.com - Predict not only the stock market, but higher power occurences like hurricanes that can impact the economy.
Jambaz.com - This service lets you predict the stock market, and the more you're right, the more of a trusted member you become.
Motley Fool Caps - From the infamous Motley Fool, get together with other stock market aficionados and try to predict where the market is going.
PredictWallStreet.com - A simple prediction site where you enter a ticker symbol, press the red or green button, and see what the majority picks on that stock for the next day.
TheUpDown.com - Get together with other stock market enthusiasts and try to predict where the market is going.
WallStreetIdol.com - Predict the future of the stock market, manage your virtual portfolio and compete with others.
FantasyMoguls.com - See if you can run the film industry better than the people running the studios.
HSX.com - Hollywood Stock Exchange has been around for what seems like forever. It is a stock market based on movies as stocks and actor's careers as bonds.
InTrade.com - A prediction/fantasy stock market about US politics.
MediaPredict.com - See if you can predict various aspects of the mass media such as TV shows, music, and movies.
NewsFutures.com - Try hand at predicting any of the future big news stories such as the capture of Osama Bin Laden.
Predictify.com - Predict future events, increase your reputation, and eventually get paid for your correct predictions.
TheWSX.com - The Washington Stock Exchange is a place where you can try to predict everything relates to US politics.
Trendio.com -Trade fake stocks as you predict vents from holidays, computer software, news, and more.
VoteKast.com - Try to predict big things like the election or the little things like which came first, the chicken or the egg.
Yahoo! Buzz Game - Precict future trends in technology and gadgets.
ZiiTrend.com - Join with other â€œZiibosâ€ and predict future events. The site will let you see how correct everyone was once the event passes.
OddsBreakers.com - Predictions and picks for the NFL, MLB, NBA, and more.
ProTrade.com - A fantasy sports â€œstock marketâ€ where you buy and sell teams and players, and attempt to predict their seasons.
SportsPoll.co.uk - A UK based sports prediction site for horse racing and football.
Xufe.com - Dedicated specifically to football (soccer). Try to predict the outcome of matches and see how the group ranks against the published odds. (via)