A pen pal (pen friend) is an old tradition but one which has proved to be invaluable when teaching youngsters how to learn a foreign language.Pen pals are a great way to learn about another language or culture.
At mylanguageexchange.com you can find a partner and practice your second language with a native speaker who is learning your language.
At japan-guide you can sign up for free and browse for pen palls from all over the world. The site students of the world ,offers E-MAIL Pen pals International pen-friendship , Networks of friends and Virtual communities.If you prefer you can also register to "Snail Mail" Pen pals.
Besides pen pals or penfriends there are new online services offer language exchange or Virtual communities Of Language Learners. In most of them you will introduced first with the following questions : Your mother tongue , your target language , your current level in the target language and of course you have to register first.One of this site is palabea which offers to learn languages by collaborating with others using audio and visual learning materials in an innovative way.
Another one called Livemocha, in which you can take exercises in your targeted language but also help other review their text or audio exercises.You can also contribute to the community by submitting materials of your own for example : flash cards in different topics and in different languages.
There are also other ways for learning foreign language in a community and one of the famous is using skype as instant messenger.