Rb-AppScript is an event bridge between Ruby and OS X that allows you to get AppleScript-esque control in OS X. The Appscript creators claim Appscript is a 'serious alternative' to AppleScript and it certainly looks good. Check out this example:

AS.app('TextEdit').documents[1].paragraphs[1].get

The equivalent AppleScript?

tell application "TextEdit"
    get paragraph 1 of document 1
end tell

Appscript provides the system to perform remote procedure calls to OS X applications, converts values between Ruby and Apple classes, and allows developers to get full use out of OS X while still using Ruby's object oriented environment.