If you're interested in London geography, here is a Google map I call "London Rambles." I've marked as many locations as I could remember and identify in the London area. Note that you'll have to zoom in a bit closer to identify individual markers, and zoom out a few clicks to see some of the outlying markers, like Gatwick Airport.
View a larger version of London Rambles here.
Many of the individual pages in the website have maps which highlight only the category of sights covered.