[jimdanz]

"It's illegal in California to have a non-compete clause." Not quite. They're just unenforceable. http://en.wikipedia.org/wiki/Non-compete_clause#California

"It also only applies if one is fired from said previous employer, not one who's left at will."

?

Are you referring to California here, or non-competes in general? If the latter, I'm, pretty sure that you're incorrect. " The use of such clauses is premised on the possibility that upon their termination or resignation, an employee might begin working for a competitor or starting a business,..." (top of same Wiki page)