Berlin is the ultimate for mine.
Hands down the best city I have visited for nightlife. It is so laid back (stay on the East side - Krysburg or something we stayed and it was boss!)
People are liberal. Girls have so much natural beauty (dont expect them to be pretentious, or wear dressed to clubs. They dress how they want, and that might be trainers and jeans!) So cheap for alcohol (and other party substances). I think i spent 600 Euro in 6 nights (and we weren't really skimping on anything). We partied so much only time we didn't even see the Wall till our train passed it on way to airport! Nightclubs open on Thursday at 10am, and shut on Monday lunchtime!!
Everynight of the week there is somewhere to go, some DJ act playing or what not. However, you have the disadvantage of being English which doesnt help in Germany. Girls wanted nothing to do with us when they thought we were (as they put it) 'arrogant English bastards' but when they found out we were Aussies they were very friendly!
Give Berlin a shout!