There's also Kepler (http://www.keplerproject.org/ http://www.keplerproject.org/), which I haven't used, and WSAPI (http://keplerproject.github.com/wsapi/ http:

There's also Kepler (http://www.keplerproject.org/ http://www.keplerproject.org/), which I haven't used, and WSAPI (http://keplerproject.github.com/wsapi/ http://keplerproject.github.com/wsapi/), which is roughly like Rack or WSGI. It's not a "web framework", but using WSAPI with FastCGI works well for CGI-ish stuff.