I backed this Kickstarter for £28 (includes £4 for shipping to the USA). Sounds like a bunch of fun over Arduino.
Micro Python is a lean and fast implementation of the Python programming language that is optimized to run on a microcontroller. The Micro Python board is a small electronic circuit board that runs the Micro Python language. The aim of this Kickstarter campaign is to make Micro Python open source software so you can use it in your own projects, and also to fund a small manufacturing run of Micro Python boards so that you can own one for yourself!