- Take one large Rails application with good Selenium test base
- Convert database configuration to use JDBC
- Start a selenium proxy with "jake test:selenium_proxy"
- Start acceptance testing from another window with "jake test:acceptance"
- In yet another window, write "jconsole"
- Choose your application

You get this for free, just by running JRuby with Java 6. You can attach to any Java process at all. Remotely too. And get this kind of information. Can your Ruby do that?
