My wife and I did a pub crawl that starts by the university of London kinda south of it a bit. I can't recall the exact place, but from yahoo it's the first website under London pub crawl and advertised on most of the tourist maps they give away in hotels. It's still my wife's favorite vacation things we've done. For more wholesome adventures try Tower of London (only for history nerds... Wife wanted to gouge her eyes out) or the huge food market (on Saturdays) just south of there, across the bridge. It's pretty famous. Unlike Rome and many other European cities, I felt London closed early. Good luck getting into museums after 5 or dinner after 10.