I used TwitterSheep to get this quick snapshot of how the people I follow on Twitter describe themselves.
In my case, this pretty much gels with what I already know. Though I was a bit surprised that “entrepreneurs” was so small. And while I’m tracking some athletes, I’ve put most of them on a list–and they’re largely not people I’m officially following.
You can also use this handy tool to peek in on your competitors to see who they’re interacting with (or at least lurking around). You might learn something unexpected.