I'm going with 3 friends. Any cool places we need to visit? Any Berliners here who can make recommendations?

Probably not. Germany is a dangerous place.

Go to Oranienburger street for some good times

I'm going to move to Berlin permanently next month.

Lots of cool places, but I don't know any secrets stuff.

Alexanderplatz with the TV tower
Unter den Linden
Kurfürstendamm
Kaufhaus des Westens -KaDeWe- (though IMO a bit overrated. Near the Kurfürstendamm)
Brandenburger Tor (Siegessäule is not far from it)
Reichstag (which is right next to my new employer...)
Olympiastadion (and the Olympic area around it)
Checkpoint Charlie
Potsdamer Platz with the Sony Center (they serve great beer there)
Museum Island (you don't have to go into any, but these are certainly nice buildings)

maybe also the Holocaust Memorial, though I wouldn't consider that fun >.>

EDIT: The Berlin Central Station is also a nice sight and has lots of shops.

I have nothing to add, but have a great time!

Yeah.. I doubt Chrizum is going for the cultural stuff.. Panaroma bar, Waterfront, Cookies, Renate and White Trash Fat Food for the clubs.. And fur die currywurst: Konnopke's ImbiS

Have a nice trip. I'm Brazilian and Berlin is probably my next destination in Europe. I've already known most of France, Rome, other parts of Italy and Vienna. Also, I've been studying German for some time and if ther is any German I could write to or trade messages with, I'd be very glad. This is why the thread came to my attention.

My favorite city!

How much time do you have? I would say Berlin is perfect for history lovers like me. Starting at the Reichstag and Brandenburg Tur and just walking down Unter Den Linden to Alexanderplatz was a treat to me. Also, check out the cross walk lights for the Ample Mann. The east is far more interesting, but the west has some beautiful parts.