Red, Yellow, Green
I've been using Mac OS X for several months now, and it just dawned on me. You know the red, yellow and green colors used for the close, minimize and zoom buttons? They look like this:

Sure, those colors may be commonly associated with "stop", "slow" and "go". But I think they were picked because they're the colors for the common apples-- red, yellow and green.
Okay, maybe not. But you never know.
What a lovely thought. It had actually never occurred to me. Perhaps this is part of Apple's auspicious thinking, in that it suggests new and other things. I can't remember ever having been inspired by a PC.
The sad thing about these is that they are arranged the way they are - the Windows way. Under Mac OS 'Classic', you never accidentally closed a window you just wanted to toggle size.
Has been said before, I know.
I never did have much use for those yellow apples... they just weren't right by me.
Have to agree with Christian about the placement. I use skins for WindowBlinds that let me change that. No matter how clever they get with up-arrows, green lights or red apples, it's just asking for trouble to have an irreversible function next to a commonly used reversible one.
Or, I suppose they could make "close" a reversible function. Close the window... but leave the app in memory for 10 seconds, giving the user time to hit the "oh crap, my GUI is somewhat less than intuitive!" button.
Mark, do you seriously want to know how many times I've actually looked for "Undo Close Window"? Esp. when it's Safari, I have ten or twelve tabs open, and I overshoot the Back button and land on the red apple. And then... it's all gone! Sad, sad, sad.
Becky: you ought to try Opera, which has an Undo Close Window button.
Opera 7.5 (for Mac/Linux/Windows) is in beta now at http://my.opera.com/forums/showthread.php?threadid=50475
TjL
(click my name for 30 days to becoming an Opera Lover)
mine are just grey does anyone know how to change them back to colors?? mark
@Anonymous: Yes-- you're using the "Graphite" appearance option. Go to the "Appearance" control panel in your system preferences and change that first option back to "Blue" (meaning, color instead of monochrome).