Retrosheet
Retrosheet is a not-for-profit web site that benevolantly provides historical play-by-play and boxscore data for as many historical seasons and games as they can find. They provide data files that are downloadable and easily useable. TBC has taken advantage of this data and included it in the site and provided some functionality around it including enhanced boxscores, game logs, historical lineups, on this day and starting pitcher logs. Not to mention the
Research Applications that use this data.