This website only provides ten Japanese lessons, but it is still a good choice if you want to learn the basics of the Japanese Language. It teaches you Japanese alphabet (including Hiragana and Katakana) as well as Kanji, vocabulary, grammar, sentences structure and some useful phrases.
Get started at: 
freejapaneselessons.com
Byki is a powerful and personalized free language-learning system and it’s available in over 70 languages. Learn different languages in a faster and better way. Finding good resources and sharing the learning with other users in the online community. It runs under Windows XP, Mac, PocketPC and Palm. The “Express” version is free and covers beginners level. This is a full learning methods that focused on the most commonly used vocabulary and common expressions. The method is based on flash card and help you to build your own vocabulary quickly.
You can give it a try at Byki.com
