Hi,
I'm trying to help a friend of mine plan a 3 month tour around Europe - she's a very different kind of traveller than I am (I prefer nature, quaint towns, etc) - she wants exciting cities with nightlife.
I'm studying to be a travel agent so I have good general knowledge of most cities, even though I've only been to London/Paris/Vienna/Venice out of the ones I'm recommending.
I'll probably recommend the major ones - London, Paris, Rome, Vienna, Berlin, Munich, Madrid, Barcelona, Venice, along with Nice and Biarritz for some beach time.
Anyone have any other ideas of places that would fit the bill?

Oh, and Amsterdam of course.

Prague and Barcelona would top my list, but not Venice for nitelife.

Milan and Rome.

Antwerp.

Barcelona, Lisbon, Sevilla, Prague

I'm partial to Paris, even though the club scene is almost non-existent. My husband loves Copenhagen and Barcelona in the summer. Venice is pretty lame. If she's visiting Paris, here's a list of my favorite bars:

http://www.parisescapes.com/paris_bars.html

Yah, I know there's not much in Venice for nightlife - but everyone has to see Venice! I'm going to recommend that she at least spend a day or two there, because she wants to go to exciting places, but she can appreciate culture and beauty too. And when you're travelling for that long you need some down time!

What about Budapest?

Definetly not Venice lol. Venice has no night life! Amsterdam rocks! Rome was a blast at night. Nice and Cannes are fun on a smaller scale although the people in Cannes were very snobby. I was bored in Paris in the evening. Madrid was a blast!

I heard Berlin is off the hook. I heard Vienna is quiet. I am actually going to Vienna in 2 weeks so if you hear of any fun things in Vienna please pass it along to me.

Oh and I has a blast in Milan at night but during the day there is not much to look at. No old world charm

When is your friend going, because you should try to see if it coincides with any of the major festivals. Octoberfest in Munich is really can't miss, and Venice for Carnivale is supposed to be amazing (but obviously in two totally different time periods). Plus I just got back from San Fermin in Pamplona which was completely insane, but your friend's trip would have to be a year from now to hit that one!
Also- what about some of the islands- either Greece (like Santorini or Ios) or one of the Balearic islands? There you get both beautiful beaches and good nightlife!

Carnival = Fasnacht

The weekend before lent is MAJOR party time in Lucerne. Date: Feb 15-20, 2007

Basler Fasnacht is HIGHLY recommended as well: February 26-28, 2007

You'll see costumes, guugemusik (costumed "amateur" bands), parades and tons of people. Festivities start early in the morning and many people stay up all night.

For nightlife, it has to be Newcastle-Upon-Tyne as rated by the 2006 Rough Guide to the UK as the Number 1 attraction in the UK

Its every night of the week but especially Thursday thru to Sunday.

Similar to Carnivale, you'll see plenty of costumes, some barely legal, lots of amateur folk singing and plenty of friendly banter, which you won't understand.

Geordie

My Top 10 in terms of fun clubs and bars and people and staying out late,late,late.

Reykavik, Prague, Ibiza, Talinn, Zagreb, London, Paris, Barcelona, Amsterdam, Berlin.

If, by nightlife, you simply mean good restaurants, well, that is another list entirely.

Ah...a subject close to my heart.
As a rule, the bigger the city the 'worse' the nightlife. I say 'worse' because big cities such as London, Rome and Paris are just so damn huge that they have very little nightlife in what you may call the tourist centres. The action tends to happen in local areas that you may, or may not, be lucky enough to stumble across.
I have a preference for 'middle sized' European cities where the centre of town is the place to be. I've had much more fun in Valencia, Reykjavik, Manchester, Vilnius, Riga, Dusseldorf, Edinburgh, Dublin and Copenhagen than I've ever had any of the 'major' cities (although Berlin is a massive exception).
Oh, and as much as I love Italy, I've never found that they have much of a nightlife culture there. Restaurants and gelato, yes, but roaring nightlife...eh, no.
And Amsterdam is just downright tacky.

I do second the recommendation of Riga, Latvia. Gorgeous clubs of all kinds and relatively cheap drinks (although expensive for Eastern European standards).

I definitely want to throw in my hometown of Hamburg. Also loads of bars, clubs all over the city center - and exessive nightlife all in one spot gathered around Reeperbahn, one of Europe's most (in)famous redilight district, which has been converted into the city's favorite weekend hangout with lots of fun and even traditonal bars, funky stuff and - yes - still a bit sleazy at times but thereby keeping its authenticity. End your night out with a fun Sunday morning visit to the famous Fish Market, where all sorts of groceries are being sold at bargain prices by the river and live Jazz is being played at the auction hall. You'd be amazed at how good a beer at 7 a.m. can taste !