I've heard of or used Webmachine, Hop, Opa, etc. What are some others and which are your favorites and why?
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 :)
Yammer is using it for it's file uploads service.
It's got a great website and it's docs aren't bad either.