In any brushed metal app, you can drag windows by any brushed metal area that isn't a control. Dragging windows by edges other than the title bar had been something I missed about OS 9, but I've become conditioned not to try, and the need had probably been made obsolete since we can no longer drag a window beneath the menu bar. I accidentally discovered this, have never heard this mentioned, and wonder if this has always been so (running 10.2.3).
[Editor's note: I had noticed this, but until reading this hint, I had not noticed that it's truly any metal part. You can drag the Safari window around, for instance, by dragging on the thin metal status bar (if you have it enabled) at the bottom of the window.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20030120065146536