can't say I like the look of Antec's HTPC cases
Lian-Li has 3 that accept ATX motherboards, but apart from the fact that they're all pretty expensive they're also quite large as well ... which wouldn't be an issue for HTPC use but most pc gamers use a desk next to which a tower is the most logical option
got a Silverstone LC17 downstairs and I like it, but mostly because it looks really discrete and blends in next to the receiver
I agree a lot of towers these days don't look that good, but there are no HTPC cases that offer the same space or cooling at an equally low price while better looking
edit: and I wouldnt install a multi-gpu setup in even the best HTPC cases, as they barely have frontal ventilation because of the "better looking" solid front ... nothing is impossible but I think it is pretty clear why most people wouldn't consider it