I've had casual OB games go about 3 hours.  My longest recorded game was a 30 min game here that went 83 moves.

I have a online game that I have been playing for almost two years now.   

My longest otb game was somewhere around six hours and finished at midnight in a draw.  Longest (recorded) game was somewhere around 94 moves or so.

My longest livechess game in time was around three hours.  If you are talking about moves, back when I played atomic regularly and kept with the theory, I had a game go 260 moves before it was agreed a draw.