The title theme is the only song we get to hear week after week, but it's still worth listening to even after two and a half seasons. And I know there are a lot of fans out there who learn to play the theme song on a variety of instruments.
Superpancho worked out a great version of the title theme for trumpet. If you're a trumpet player, check out the sheet music! You can give it a try yourself. Many thanks to Superpancho!