Ever since I was a little tyke, I have had a special fondness for bad guys who dress like the heroes they fight. I mean, what's more disrespectful than wearing your enemy's trademark design, only screwing with the colors? Only a true badass can do that and get away with it!
I never really understood why the Composite Superman made his skin green, but he made himself an abomination of the Big Two so you just knew he could (and did) cause them major problems. If Superman had more bad guys like the Composite Superman, a Superman story might be interesting every once in a while....
The first bad guy who I can remember making the ultimate fashion statement is Professor Zoom. I mean, up above you have the Flash. Down below, we have the exact opposite colors, right down to the circle that supports the chest insignia. How could he help but be Flash's greatest adversary?
And yes, I count the current version of Zoom as awesome. If I seem him on the cover, I must read the story. Even if it's in Wonder Woman's title...
Black Adam. So badass he doesn't even need the cape most of the time.
Sinestro has always been an interesting foe for Green Lantern, but I always wondered why, since he hated the Green Lantern Corps so much, he didn't wear a uniform that reflected that.
Then, along comes the Sinestro Corps....
..... oh yeah. That's the good stuff right there.
I remember reading a Neal Adams drawn story with a Superman and Batman Revenge Squad where Superman's foes had a costume exactly like his except a green insignia, and Batman's enemies wore a purple version of his outfit with a winged skull emblem (which I, at 10, thought was quite awesome). Who else am I forgetting?