Same here OP.
Well sorta. Started with a 486 desktop, then bought a Directwave which was a mid-tower. Then finally built my own in a huge Inwin Q500a full-tower (this case is still around today housing my parents rig). Then I upgraded but kept the full-tower. Then off to college so I ended up with a cheap, POS Raidmax with a lovely human window. I still have it cause I'm too lazy to find something new.
When I upgraded in Feb to a Opty + 7800GT I wanted to get a SFF case. But the Shuttle XPCs are ridiculously overpriced, and though the Aspire Qpacks are sweet, they are a little pricey after you need to toss that crap PSU in there and get your own anyway. BUt mostly I was worried about reading things that people said high-end video cards wouldn't fit in there, not enough room for good cooling, etc.
But I run pretty minimal. One PCI-E card, Audigy Platinum taking up two PCI slots unfortunately, but that's it. Two hard drives, one optical.
I still might try out a Qpack or something similar cause SFF would rock. If not I just want to get a quiet, light (possibly aluminum) mini or small mid-tower. I originally went to a full-tower since it was a PITA working in cramped mini-towers and whatnot, but now I can deal with it, plus if I get a SATA drive finally that'll make it easy. And I could bring one of the PATA drives out to an external enclosure.
So I think I could make a SFF case work. But wait, I bought a ATX mobo... there was hardly any worthy NF4 mATX boards. So I guess I need to find a quiet and smallest mid-tower I can find.