As of today, you can now watch basically any game in HD on your TV if you're an MLB.tv subscriber ($20/mo, I think?) and you buy a $99 Apple TV. I would think this is a no-brainer for anybody who's a fan of a team outside the market he lives in. Enjoy Spring Training games and regular season games on Apple TV | MLB.com: Subscriptions
EDIT: Okay, I just figured out that apparently this was already available with a Roku box. Still, the fact that you can do this is fantastic. Cardinals fan living in East Tennessee? Watch all their games on your TV. Padres fan living in Florida? Watch all their games. Yankees fan in Colorado? Watch all their games. This is great.