Written in Python using PyQt4 GraphCutie is simply a graphing calculator. It starts up quickly and produces simple results that you can save and use elsewhere. The interface is very similar to a TI-83 calculator.
It is completely free, open source and many of the notes I use for qt are kept here on this site. So check out the screenshots. If you browser supports svg, there is even an example of a graph. If you have questions email firstname.lastname@example.org