Hi all,

Next week, I need to be in London for work (read: afternoon tea) one day, and I'll have 2-3 hours spare time in between.

I need this forum for suggestions, tips, things to do in a hurry, that are not commonly recommended for tourists: alternatives.
(since I've been visiting London already a few times and have been visiting the main tourists traps already)

So, what does a local (points the finger at you) in the city when you have nothing to do?
Recommended funny shops, bars, exhibitions, offline geek stores, ...

Thanks in advance!