I feel browing through API is just painfully slow, so I just put on a
new site (done totally in ROR and jQuery) that supports quick search
of Ruby, Rails API
Hopefully it will be helpful to others.
http://www.railsbrain.com/ and http://www.rubybrain.com/ are also ajax
based api documentations that support search and even allow you to
download whole documentation and contribute to it using git.