Scratch all that ^, it's a town (almost embarassingly nowadays) made for British Stag do's, with corresponding night activities.
There are small bit's of stunning original architectre that let's face it will not even get a look in in your 24 hour bender that will be either a celebration carry on of momentus proportions, or a drowning of sorrows of equal measure. For that purpose there are more than enough bars!
I would recommend starting off however, in the Syline bar, which is unmissable as a 40 odd storey hotel with a bar at the top (you don't have to stay at the hotel to drink in the bar) walk down into town you'll eventually stumble upon a square with quite a few bits going on around it, and a very good Argentinian steak house (wholeheartedly recommended).
Clubwise we only went to a massive cheesy-ish disco (though we had Prydz playing when I was out there!) who's name excapes me that was on a corner just a short walk from the main drag (and round the corner from the previously mentioned Skyline bar).
Be warned, the locals make the British women look rather ugly!
Alll in all it's a very accomodating place (with regards to handling drunken guys!), due to the explosion of the stag do trade. PLus it's certainly not as dangerous or dare I say scary as other Eastern European towns I've been to.
Of course, this could all be wrong, and if anyone wants a guide to Vilnius in Lithuania, then this could also be it as I went to both quite close to each other and have been known to get the two confused!