EasyPortuguese	Portuguese lessons, useful phrases, audio samples, vocabulary, alphabeth, etc.
Interlex	A free Windows application that can help you learn vocabulary in a foreign language. The program is built around a simple idea: first you compile a list of words and phrases, then you test yourself until you have learnt them.
Learn Mandarin Chinese	25 free online Mandarin Chinese lessons.
UsingEnglish.com	Provides a large collection of English as a Second Language (ESL) tools & resources such as: a grammar glossary and references of irregular verbs, phrasal verbs and idioms, ESL forums, articles, teacher handouts and printables, links and information.