Oh for fuck's sake...
Not trying to be an ass but a breaker bar will friggin' work. There's only two end results, either the nut/bolt will come off or you'll be posting on here about a broken nut/bolt. Since you haven't posted any such thing you therefore have not done too good a job with the breaker bar. I'm not talking about a damned ratchet (who the hell is stupid enough to try using a ratchet? It'll kill the gear mechanism) I'm talking about an actual breaker bar. Just run to any auto part store and pick up a nice two-foot long breaker bar (a long metal rod with a socket accepter on the end). Put it on the nut/bolt and put some muscle into it. If it still doesn't work, grab a length of pipe, slide it over, and try again. If it still doesn't work or nothing has broken, try again, and again, and again...