I was thinking about this lately, but I always loved the look of the PS2. I I think the black and blue color scheme works really well. And I like the two levels like the top and the bottom part of it.
Second to this, I think the Dreamcast looks really great. The angles on it make the console look so compact. The orange light on the console is placed really well too.
What do you like?
The GameCube in a cool color (like Spice Orange). Not just because I like orange. It has great contrast with the grey and black parts of the console. And the whole thing is wrapped up in a tidy, aptly-named package!