What are the current web framworks that are well thought of an supported? 
Preferably compatable with MRI & jRuby.

I'm trying to help a coworker.  Rails is way to big and not really a good 
fit.  So far I have recommended Sinatra as a possibility.  What else 
should I suggest as worthy of a look?

-- Matt
It's not what I know that counts.
It's what I can remember in time to use.