Have you never GM’d? Have you GM’d only a little? Have you just be kinda curious about GMing and, along those lines, GMing indie hippy games like Primetime Adventures or The Mountain Witch?
Are you a vet GM with lots of ‘trad’ experience, looking to spread the authority of the GM around a little bit, or just get a little more ‘play’ time?
Read this thread: Story Games for Everybody – Calling all Non-GM’s — it’s a good poll of folks who don’t usually GM who have tried out the reins with indie/hippy games of various kinds, what they’ve found they’ve liked and don’t like. Good, good stuff.