Today, Urbit has chat, blogging, a basic weather app, and a lot of programming facilities. Eventually it should be able to run a document editor, and you can do things similar to internet browsing even on today's Urbit.

Urbit is a long-term project starting from the foundations and working up the stack. It'll be stable soon, but it probably won't be ready to run something as heavy as a modern web browser for a while. That being said, it does work, and it's fun to play with as-is.