Wezzy, I'm off to merry old London in a few days. Anything to see tourists don't know about?
H'mmm....i'll have to think a bit more about this, but for now:
Try and get to London Bridge on a Saturday morning and start off at Borough Market (great place for street food) and buzz, then walk along the Thames river walk towards Westminster Bridge, Tate Modern is worth a quick look (try and get to the skyline view in the new building), SouthBank Festival Hall (more yummy food around the back of it), and the street entertainment along the walk to the Millenium Wheel, then you hit tourist town by Westminster Bridge. This walk can take anything from an hour to a day depending on what you stop to do. It's a great walk and you see a lot of London.
If you still have energy at Westminster Bridge cross over onto the North side to Parliment Square and get to St James Park and walk through it to the Palace. From there come back through Green Park to Piccadilly Circus and then you are in the heart of London.
You can do the whole route and not spend a penny...or spend a fortune...your choice