Do you have a favourite/nightmare place to ride in London?

noggin Nightmare:
+1 for the Elephant & Castle r'bout (~£1k of dental work after a car-bike-tooth-tarmac incident in 2002... still wary)
Kennington Park NE from Oval to Kennington tube (down the white line with 2 lanes of maniacs on either side)
The Wands-way System (all of it really).

Ha the white line of death! I have a love hate relationship with that every morning, similar going the other way when you have to get over to the right hand lane as it splits into 3, then always trying to beat the lights at the Junction outside Oval station - only managed it a couple of times and you have to be going some to do it.