iPython is a really great tool for working with Python interactively but its less than awesome on Leopard. Why you might ask? Well, included in the list of sins Apple has comitted with Leopard's terminal environment was shipping a broken version of readline. The good news is it's easy to fix! The iPython folks have a version of readline that works on Leopard. Just easy_install it and rock out with full readline support, including working home and end keys.

sudo easy_install -f http://ipython.scipy.org/dist readline