One of the most difficult things for those self-studying languages is getting your written work corrected, especially if you don’t have a friend who is fluent in the language you are learning. lang-8 is designed to solve this problem.
lang-8 allows you to write blog posts/entries in your target language, and other lang-8 users who are native speakers correct your posts. So far I’ve found the site immensely useful, especially when I was practicing for the written component of my Polish exam. By having native speakers correct your work, you’ll end up with more natural writing in your target language and learn for your mistakes.
Keep in mind though that the site works on the premise that in return for receiving corrections you in turn correct entries from other users in your native language. This can be difficult, as often you don’t think about your own language’s grammar and formal structure, however it’s worth putting the time in in return for corrections on your own work.
Overall, lang-8 is a great resource for writing practise in you target language