I was talking to a buddy about this idea yesterday, and he came up with another cool "ownership" idea: Own a Rock Band. Kinda a cool twist on the same idea, but would require a far smaller investment. Basically get like 1,000 people to put down a buck or two, and then have a battle of the bands in a local area (and pay the band a portion of that take). Then, raise some more money to get them some studio recording time, and then launch the CD. The "owners" could each state what their favorite songs were, what the CD art should look like, etc.
Obviously it's a rough idea... But it's an idea. And it'd cost a helluva lot less than owning a major sports franchise.
Alright, someone go get it started.