The British Council – loads of great stuff – podcasts, magazine, fun and games, exam preparation help, business resources.
BBC – videos, articles, lessons and more.
Learn English Free Online – good for British English and culture, plus other helpful resources on vocabulary.
Engspeak – another blog, with some great posts and advice
The English Blog – explains news articles, provides videos, reviews, tips and trivia to help you learn English.
Voice of America – although I’m biased about Britain, we have to admit that this site is good. It’s full of articles about English and American life and culture which are set to appropriate levels and have post reading and -listening activities. It has interactive learning programmes, and idiom dictionary, a wordbook, and videos. Definitely worth a look.