On the topic of _distinct_ frames... I've made a simple tool [1] that specifically generates a sequence of highly distinct frames, which can be useful to do various tests on LCD/CRT monitors.

[1]: https://github.com/shurcooL/RefreshRateMultitool / http://hardforum.com/showthread.php?t=1423433

Btw, is it okay to plug your stuff? It's my first submission to HN so I'm not yet an expert on how things work here. I just thought it was relevant, so I wanted to share...