I'm with Stormhound on the angle of "I'd much rather tinker with a pre-existing game system than make one from scratch". In the same way, I'm much more inclined to play a system that has its basis in something already published.
However, I'm very open-minded and I will try just about any game system (even homebrews) once if that's what the group wants to do.
I also have interest in trying a wide variety of different games and systems because there is a surprising assortment of really good games out there. From Wushu to SotC, Supercrew to Dust Devils, Zorcerer of Zo to Prime Time Adventures, there is no shortage of fun, original ideas in game design.
HARRY DRESDEN — WIZARD
Lost items found. Paranormal Investigations.
Consulting. Advice. Reasonable Rates.
No Love Potions, Endless Purses, or Other Entertainment.