Meteor is kind of nuts: https://github.com/meteor/meteor, real time, database abstraction built right into the browser/js, no lag for saving as it uses background sync.
Screencast is here: http://player.vimeo.com/video/40104996
Screencast is here: http://player.vimeo.com/video/40104996
if you like coding in text editor(vim, notepad etc.) and debugging with println`s, meteor is for you :)