The Monthly London Flickr Pub do.
This month @The Bath House in Dean Street - does real ale, a good Guinness, is central, not stupidly expensive, and while it can get busy, not ridiculously so.
If it's not too hot, you'll see the Grey Trilby too!
Official Website: http://www.flickr.com/groups/londonflickrmeetups/discuss/72157622029574632/
Added by sjnewton on August 26, 2009