Baby - This site specializes in idioms and slang. Great
video and free lessons.
Duolingo - Help the world translate websites into your native language. At the same time, this might help you improve your English. This is a very interesting idea.
Exchange - Find Language Exchange partners from around the world
to practice and improve your language skills.
Planet - Learn other languages and share
your language skills with people around the world. Free site.
Conversation Exchange - Practice English with face-to- face conversation, find a penpal, or chat in text and voice. Free site but not a lot of members so far.
LiveMocha - Livemocha blends self-paced lessons, a vibrant community, and interactive tools to help you talk to the world. Definitely one of the best free sites out there.
Language for Exchange - This is a language exchange community which allows people
to make contact with users from other countries and organize their own
exchanges to learn a native language.
EasyLanguageExchange - This new site matches speakers of different languages who want to practice with each other. Your perfect match is just a click away!
Busuu - This is a free online community for learning languages. Connect with native speakers worldwide. Enhance your language learning with online languages courses.