I do know people who do it and they love it, although my opinion I wouldn't do it.
I was asked at one of Britains leading nightclubs to take photography every Sat night and for the big events with international djs. Even though this all seemed enticing, I swerved away purely on the basis of -
Not enough money, 60 pound as the above poster said, is the going rate.
Risk of equipment being stolen/damaged.
**** heads giving you a hard time.
Commitment every Sat night!!!
That being said, I have done a few wkends to cover and have enjoyed it. Just personally couldn't do it every week.
Good luck with it, I'd suggest going with 50 for your going rate and drinks chucked in.