ETLive is quite an interesting project started by few people who wanted to bring old Wolfenstein: Enemy Territory in a simpler form via web browser.
The idea is based on popular QuakeLive developed by id Software. ETLive is entirely fan based project, so it will take some time to finish, but it is most definitely worth checking out. The creators promises competetive support and a few new unique features, so it basically would be old Wolf ET with few improvements.
While the development is in progress you can follow creators blog right here: http://blog.etlive.pro/