Sailgroove is one of the coolest sailing websites out there, and it was started by a college sailor not too long ago. They have a section of 2 minute videos called Technique Tuesdays which are fantastic. Beware, once you start watching, it's hard to stop. Here are some good ones:
Basic Racing & Tactics! Not as exciting as Sailgroove.org, but it is definitely a must read, and probably the single thing more important than sailgroove! One of the best free racing tactics guides on the web.
Great way to practice rules. You might have to make an account, but it's definitely worth it, there are tons of good scenarios.
A bunch of tips on college sailing. Full of good stuff!