Covent Gardens is a fun place if you want to take portraits of street artists and people :)
I took those photos there yesterday:
http://www.photoboard.eu/photography/showphoto.php?photo=2236
http://www.photoboard.eu/photography/showphoto.php?photo=2238

There are street artists near London Eye but they are less fun than the ones in Covent Gardens.
Here is another photo taken yesterday:
http://www.photoboard.eu/photography/showphoto.php?photo=2237

All the photos were taken with the Nikon D70 with the Sigma 70-200 f2.8.