Edit: to clarify I specifically meant a front-end tool to help me leap a level in personal development skill.
I am using backbone for a while and it's backend agnostic which is great !
This one have more resemblance to knockout.js( I am talking client side) and it's MVVM design, backbone doesn't even try to approach that problem.
- meteor <- the low level of the high level :)
You use meteor as a foundation to build your application as backbone is more or less your application itself. Think "CoreFoundation" vs "AppKit" kind of difference.