I was just writing a bit about realism for my book the other day. Interfaces, such as Mac OS X's Aqua, actually represent a sort of "hyperrealism," with buttons that are impossibly juicy, reflective, and glowing.

It's funny, because interfaces have always represented reality in a metaphorical sense (desktop, window, document, trash), but now we take it up a notch to represent things that couldn't actually exist.