Duolingo is a great online protal for learning new languages online. They currently support German, Spanish, French, Portuguese, Italian and Chinese.
Here is a short explanation of Duolingo:
The inventor of duolingo, Luis von Ahn, did also a great TED-Talk in which he explains the concepts:
Now some screenshots to give you a feeling what Duolingo offers:
![Achievements in Duolingo](../images/2012/06/duolingo-advancement.png)
![Translation in Duolingo](../images/2012/06/duolingo-translation-300x155.png)
![Duolingo analyses your errors.](../images/2012/06/duolingo-typo-300x166.png)
![Speech to text task in Duolingo](../images/2012/06/duolingo-speech-300x149.png)
![Duolingo: Photo to language](../images/2012/06/duolingo-photo-to-language-300x167.png)
![Multiple choice in Duolingo](../images/2012/06/duolingo-multiple-choice-300x137.png)
![A lection in Duolingo](../images/2012/06/duolingo-lection-300x173.png)
![Level mastered ☺](../images/2012/06/duolingo-achivement-300x138.png)
I have 3 invitations left. If you like to test Duolingo, simply post a comment with your email-address. The first three will get the invitations.