englishclub.com
English Club is a Web site designed for anyone learning or teaching English as a first or foreign language. Every topic you can think of is discussed on this site, be it vocabulary, grammar or pronunciation. Many resources worth checking out.

Common Errors in English
This site contains a huge repository of the common errors made in English, be it spelling mistakes or bad pronunciation. It is very well written and contains enough information to help make sure you won’t make the same errors again.

Advanced English Lessons
This site provides free online English lessons, as well as other valuable ESL / EFL resources.

Languages and Linguistics
If you have interests in different works done about language, linguistic theory and structural linguistics, this page provide a set of resourceful links that may prove to be helpful.

English: an easy language?
And you thought learning English was as easy as counting from ten to one backwards? The author of this site does a good job of shedding light on the difficulties and inconsistencies of the English language.

The French Tutorial
For a user-friendly experience, check out the French Tutorial. Well written and easy to navigate through.

frenchlesson.org
This comprehensive site offers numerous tutorials. It is geared toward students who already have some French experience. Interactive exercises are integrated into the tutorials to facilitate the learning process.