Roll20 is an online virtual tabletop for RPGs and board games -- namely Dungeons and Dragons. On the site, you can create boards/backgrounds, characters (referred as tokens), and much more! This site is valuable because you can easily play many popular board games online with your friends. In addition, the site is easy to use and there are many official guides on their wiki!
Code Spells is a game, now in beta, that teaches basic Java programming through a game. The game has an RPG element and in order to cast spells, the player must 'program' their character to cast.
RealTutsGML has lots of tutorials, whether it be making an RPG in GameMaker, the basics in Java, or a platformer in Java. His site is absolutely amazing, and I learned so much from it.