Depending on what you want to do, you could use activemessaging (http://code.google.com/p/activemessaging/) to send messages to non-rails processes to work on asynchronously, and still get access in those asynch processes to all your rails environment godness…
For example, I use it to asynchronously process audio submitted through our website - since the processing can take ~30 minutes.
-Andrew Kuklewicz http://beginsinwonder.com
