The list would be more than most people would want to see. I am a forum junkie, and moderate a couple as well. I also have the ability to read at speeds that would astonish most people, so spend a lot of time just lurking, and not posting much.
Military History, cars (mostly Miata related these days), wargames, political discussion boards, computer hardware and others. About a dozen I visit daily at least, another 20 I go to once a week or so, and yet another 30 I hit only on occasion.