Besides being the drinking capital of the world,
Prague is also a really beautiful city and every year over 5 million tourists come to visit.
Most come for the sights like the Charle's Bridge and the Staromestke Namesti, but that shouldn't fool you into thinking that Prague can be boring. There's literally hunders of clubs, many of which are open pretty-much nonstop.
To list just a few:
Sasazu
Nebe
Mecca
Infiniti
Solidni Nejistota
And all these places let in with no ID check and sell absinth :D