In Search of the Perfect Computer Chair?

mantid asks: "Many slashdot readers are certainly sitting at computers for 8, 10, 12, even 24 hours at a time... What are you sitting on? As I get older, I realize the importance of ergonomics more and more. I've been happy with my cheap Herman Miller, but now I'm switching jobs and have to select again. How important is your seating, and what has worked for you? In high school I sat on a stool for hours as I ran a BBS but that just doesn't cut it anymore."