The 2007 edition of Shaun Sullivan's outstanding baseball text sim, PureSim, is now available for purchase here. There are a ton of improvements, but in particular, this version now includes the Lahman Database, which allows you to import real players and their associated stats from 1900-2005.
PureSim is a long-running, terrifically designed baseball game with the most flexibility of any text sim I've ever seen. Virtually every aspect of the A.I. can be comprehensively tweaked via an .xml file, and Shaun's decision to open up the engine has helped create a very robust community dedicated to the game.
You can see a nice selection of screenshots here. Shaun's made amazing strides in improving the look of the game in the last few years, and those screenshots show it clearly. It's been my favorite text sim for years, and it just keeps getting better.