English for All.

Plataformas de Ensino.

Memrise. - for Teachers.

http://www.memrise.com/courses/english/

Weblínguas.
http://www.weblinguas.com.br/

Your Language Exchange.
http://www.mylanguageexchange.com/

BBC Languages.
http://www.language-exchanges.org/

The mixxer. - via Skipe.
http://www.language-exchanges.org/

My happy Planet. - via Skype
http://www.myhappyplanet.com/

Forvo - Pronúncia
http://pt.forvo.com/

Populares:
Buzuu.
https://www.busuu.com

Colingo.
http://colingo.com/

Babbel.
http://pt.babbel.com/

Plataforma Lattes.
http://lattes.cnpq.br/