I spent part of the morning goofing around with Shoes. It's a very simple GUI toolkit from _why, the guy who wrote Why's Poignant Guide to Ruby. Although the docs have the wackiness you would predict ...

Scripted GUI Testing with Ruby--New from Pragmatic Bookshelf How to Test User Interfaces Reliably and Repeatedly Raleigh, NC-If you need to automatically test a user interface, this book is for you.