Hello
I just released an update of my FirePHRuby script for AJAX development
with Firebug/FirePHP. It can display all basic Ruby types now as an
experimental option. Have a look at a nice screenshot on
http://firephruby.rubyforge.org/ .
It is easy to install via Rubygems and works with Rails as well as in
CGI environment or with plain WEBrick or Mongrel.
T.