Baseball
http://baseball.sportsline.com/
Who you draft on your Fantasy Baseball team is the most important key to winning your league
http://www.sportingnews.com/
Play for FREE! Build the best team you can buy under the salary cap. Dynamic player market lets you buy and sell players to improve your franchise.
http://mlb.mlb.com/
Put together a 57-game hit streak for your chance to win $1 million.
Basketball
http://nbase.nba.com/ 
The NBA Stock Exchange (NBASE) is a fantasy basketball game where users become the general manager of their own team of professional Basketball players. The object of the game is to score as many fantasy points as possible by assembling a team of NBA players.
Golf
http://golfinvestors.com/
The collection of stock markets which GolfInvestors runs contain both real and fantasy (simulation) markets. These markets enable investors to buy and sell shares of professional golfers and professional golfers to raise money for their tournament golf endeavors.
More fantasy sports games
http://sports.yahoo.com/fantasy 
Different fantasy sports games on yahoo!
http://www.sportsline.com/
Baseball, Basketball, Golf, Racing, Hockey, Football.
http://www.fanball.com/
Football, MLB, Basketball, Hockey.
http://fannation.com/
http://www.protrade.com/
- cash out for cool rewards
- compete against other traders for prizes and bragging rights
- plus, it's free, fun and addective
http://www.fantasysportsstocks.com/
Buy low, Sell high - It's simple...pick the winners and earn lots of points for prizes. Buy the underdog for cheap and cash in big...or...pick the favorite and earn smaller gains
http://www.rotohog.com/
- make daily moves at the trading floor
- play yout friends and see how you stack up agains the world
- win big prizes