My friends know of my strong obsession with the EA/Harmonix video game 'Rock Band'. I'm a huge fan of this game, but not just because it's a lot of fun. The game provides a level of immersion that hides the instructive side very effectively. Simply put, you learn key musical building blocks--rhythm, pitch, and coordination--without even realizing it. I think we're seeing the start of something really revolutionary that will lead to an explosion in musical talent and interest.
Just look at how people are using Rock Band to teach themselves how to play real drums. Amazing!
Thanks to Victor for the link.