Created after the demise of, and with the blessing, of londonfreelist.com the site also aims to have comprehensive political/activist listings. Load up your own political event or send details to editor (at) freelondonlisting (dot) co (dot) uk
http://www.freelondonevents.org/events-categories/categoryevents/20-Politics/Social%20Action.html
Other features include a forum and a resource section with practical advice on housing, benefits etc is on the way.
There will also shortly be a section added for benefit events which do not have to be free.
The site is still in Beta so all feedback is very welcome
http://freelondonlistings.co.uk/