I've stayed awake for 48 hours. Wasn't tired, but forced myself to go to sleep anyway cos' I was bored. I could have stayed up another 24, probably. That was during summertime though, a few years ago. School screws things up ^_^

Anyway you'll probably be too tired after a while of that. Don't overdo it just to get a "sense of achievement," there are other things to achieve :P