The great thing about Baseball Almanac.com is that they view the game in a historic perspective. It doesn't matter if you're a fan of the Yankees, Red Sox, Braves or any other American or National League team, you'll discover an incredible amount of information. Even if you don't root for a 'favorite' team and are just a fan of the game you can find links to pages of facts that you have probably never known before.
Want to know about baseball movies, World Series or All-star games of the past? How about overviews of past seasons? BA has all that and more. Whether you are really into the stats or just want to know a little about a player you followed as a kid the BA writers & researchers will probably have what you are looking for.
This is the first baseball link I'm going to be adding and probably one of the most inclusive.