A couple of weeks ago I survived all the way through one of the 2000 entrant all-in fests to win. Made $10. Not a lot per hour...but the thrill of the win was great!
The key, I think, is to be patient as hell at the beginning. People are constantly going all in with anything (or nothing, more properly). Save your all-ins for a monster hand. Then, when the crazies weed themselves out, you can play a bit more aggressively. Plus, with any tourney of that size...you have to have some luck on your side!