I've seen a couple that look good for airflow and build at the sake of looking not as good as the Prodigy M and Parvum S2.
In-Win BR665 and In-Win Dragon Slayer
http://www.overclockers.co.uk/showproduct.php?prodid=CA-009-IW
http://www.overclockers.co.uk/showproduct.php?prodid=CA-010-IW&groupid=2362&catid=2278
I've heard good things about In-Win and the airflow looks great on these but I haven't checked a revew of them yet. While they don't look as good, their price point and build quality looks good. Any opinions on them?
(I love the look of the Prodigy M but I'm worried about the build with how cramped it looks and the Parvum comes at a premium price. With a compromise on the case, there's a bit more money for components.)