I know some of
are planning on trying to catch the Tour de France on Saturday or Sunday.
There's a fantastic short film up that shows the prologue route for Saturday and the best places to watch from.
Hyde Park is likely to be your best bet, there will be a whole heap of other things going on there as well as the actual racing. From what I understand the publicty caravan will be around at lunchtime and then at 14:00 the riders will use the course to warm up. The official start is 15:00 and the last rider should have completed his lap at 18:20.
There's loads more information
here including more details of Stage One from London to Canterbury.
*will remember to breathe*