A current favourite is 80s London Squatters, as the name suggests including loads of photos of London punks and squatters and their hangouts around that time. There's some good South London stuff on there, like this:
The photo above is of Brixton Lido in Brockwell Park. Considering how busy that place is now in the summer, people may be surprised to know that Lambeth Council closed it down in the early 1990s. For a while it was squatted, I believe from Summer 1993. People lived in the changing rooms and offices around the pool, and they hosted various events including cabaret nights, Brixton Poets Society, cabaret nights, a couple of rave-parties, an end-of-tour party for The Levellers and an Exploding Cinema film night in August '93 that attracted more than 2000 people.
I went there a couple of times in this period, and the pool was empty. But as this photo by Fleur Daniel shows, they did manage to refill the pool at some point. Who knows, perhaps they helped save the pool from being sold off, since the events they held there created a buzz and momentum that others were able to build on when plans were being floated (pardon the pun) to reopen it as a Lido.
Another piece of South London history I found there was this flyer for a 1989 All London Squatters meeting at 362 Old Kent Road. This was a formerly empty shop squatted and used as a base for SNOW (Squatters Network of Walworth) from 1985 until late 1989 - by which time SNOW had been superseded by SHIP (Southwark Homeless Information Project). The latter moved in 1990 to 612 Old Kent Road, this time as rent paying tenants. This was a period in which huge numbers of homes were left empty across London by councils and other landlords - a vacuum that was filled by (mainly) young people taking over empties and turning them into homes. In Southwark alone there were 1600 squatted properties in early 1988.