I have been looking around for sites on which I can generate some extra cash for writing, with varying degrees of success.

Here's my question: What do you folks think of sites that require exclusive content from their contributors?

In some cases, I'm OK with it. McSweeney's, for example, is a site that I plan to submit to eventually, and I don't mind that they require content exclusivity. They have the reputation to back it up, and although they don't offer compensation, the exposure would be great. That and the fact that Dave Eggers is behind McSweeney's, and he is on my top five living writers list.

In other cases, I'm not so sure. Triond, for example, rejected a piece that I wrote because it appeared on my blog (I didn't read the rules very closely, apparently). With so many fly-by-night companies, and companies that really don't have the pull to be able to get anything back to the writer for their effort, I am pretty skeptical.