check out
www.frozencpu.com for some cool case ideas, I've bought from those guys before and they seem to be pretty good.
edit: maybe something like an acrylic case. C3 and AeroCool put out some good clear cases.
If clear isn't your style, maybe a Chenbro Xpider case or a blue X-Dreamer II.
I work for a computer store as a tech and these are some of the non-standard cases that we use when the customer gets tired of the same old thing