What's the correlation between FIDE rating and online rating? I'm wondering if there's any way to get an approximation of my FIDE rating by using one of my online ratings, say ICC or chess.com rating? If not, is there, at least, a correlation between how well you rank on those sites and your eventual FIDE rank?
I asked this on ICC once and was directed to the following link:

http://www.chessclub.com/help/ratings

IMHO, I don't think there is a fail-safe way to approximate a FIDE rating based on online ratings.