Pretty fun, but not very realistic in the sense that the trade is taken exactly after 10 or 20 days. You don't allow setting stop losses, etc. Chartarcade.com

Pretty fun, but not very realistic in the sense that the trade is taken exactly after 10 or 20 days. You don't allow setting stop losses, etc. Chartarcade.com is a really good stock simulator. It's been around for a while, also uses real stock data, and allows you to buy and sell while incrementing on a per-day or per-week basis. It's actually a really good tool for learning how to buy and sell stocks on a swing basis.