This week whilst thinking about how to represent an idea as a GUI application I ran into the limits of GTK3. I had a look around at matplotlib and pygame as possible work arounds but neither suited what I had in mind. It was then that I discovered Kivy.
Kivy - Open source Python library for rapid development of applications
that make use of innovative user interfaces, such as multi-touch apps.
Having had a look at some of the demo interfaces that have been created it looks like a really powerful tool. The only limitation appears to be your imagination. In addition the multi-touch aspect is appealing in the longer term as touch interfaces become more prevalent. Once I can get it fully installed/working on Fedora I will be experimenting with it a little.