As you can find lot of ressources about many subjects, Internet is a good way to help you to learn.
Moreover with new possibilites like instant messenger, podcasts and collaboratifs works allowed by Web 2.0, we can say that it's possible to learn with only the web.
Concerning instant messenger as 
or 
, these softs are well created for conferences, discussions and for instant conversation. It's a good tool for a class and especially for languages.
For languages using audibook it's a good way to improve earing.
About ressources like wikipedia, a recent survey say that informations are enough right as a classical encyclopedia.
Many schools have a departement for e-learning like the University of Canterbury.
But i think to be efficience e-learning have to be managed by a teacher or a someone with pedagogical knowledge.
Tags : e-learning;msn;web 2.0