Drawing Board was probably the most usable of Apple's alternative Appearance themes (which never shipped, but were leaked pretty quickly). The little lines extending off the corners of windows had some glitchy behavior in some apps, IIRC, but it was at least visually acceptable, and I used it for a while.

The other two themes were basically unusable, though, and it's very clear why they were never officially released.

That is quite nice from a purely visual perspective.