Equities and Derivatives on Sports

I know this sounds kooky, but hear it out. I would like to see an exchange created that allows one to trade equities (and derivatives) on sports figures and sports teams. For example, let's say that I like the Spurs and I thought pre-season that they are going to kick ass. In that case, I'd long some Spurs and hold till the time is right. In the case of derivatives, if you saw the Hornets, for example, playing extremely well one could short the Hornets and play the change in their performance (hence the change in their underlying value represented by the base security (similar to a stock in this case)). A calendar option (either way) would be interesting as it might represent the performance over a span of time, like the playoffs for example. A vertical based upon a measure, points against opponents for example, could be used in that case. I think this is a very interesting idea, the only thing that scares people is the fact that the underlying security is not backed by owing a portion of a company. I think most people like the security of owning a portion of company, not sure why that matters. Most traders look to make money off of change and speculation, not holding something to own a portion of a company.

Thoughts?