In the mornings, you can join the locals in the practise of fika, which is basically enjoying a good strong coffee and a pastry. Other traditional Swedish food centres on fish - with herring and potatoes the staple.
Herring with cheese is popular, as is fermented herring, a particularly pongy dish, so just follow your nose to a nearby cafe. Another dish, palt, is made of potatoes and flour and eaten with pork and lingonberries and the Swedish are also very partial to the odd meatball or two.
Good places to eat include any kvarterskrog or krog (local pub) and the city also has some excellent, if pricey, restaurants serving modern-European-style cuisine.
There's a thriving club scene in the Swedish capital and your first port of call has to be Stureplan, where venues such as the Laroy, Koket and Spybar are the places to see and be seen. Most clubs and bars stay open until around 5am, but a word of warning - many clubs have a dress code and a minimum age limit (usually 20) and stag groups are unlikely to get into the swankier clubs where the bouncers are particularly picky.
If you're the more cultured holiday sort, you can often catch a classic Chekov, Strindberg or Ibsen play at the Royal Dramatic Theatre. If you've got ballroom dancing fever, go for a waltz at the Mlarsalen or the Gota Kallare.