Office chairs

[CarbonCycles]

Alright folks:

Thought I'd pick your brains for a bit, but can anyone recommend a really good office chair? Since most of us spend a good time at the office pushing paper and then put a decent amount of miles on the saddle, what chairs can you recommend to mitigate the effects such as tight hip flexors and such? I was staring at some of the Herman Miller stuff, but I thought I'd get the 411 from you folks before I put down that kind of cash.

TIA..