I discovered fingeryoga.com the other day. Great stuff on that site, and I was surprised to find that I already do about half of the exercises listed.
My favorite is still my old faithful, a move they call the splits. I came up with it on my own in 2004 when I had my first encounter with tendinitis. It helped then, and I still use it daily. I keep coming back to this site, trying to remember the crazier poses I liked. Some are really complex, and not for n00bs. They come in handy at work, or anywhere else that doesn't allow guitars.
Use caution. Read the warnings and start slowly. And avoid the two-handed poses while driving.