This is more of a feature than a hint, but I haven't seen this mentioned anywhere else. OS X 10.2 will now display the titles of inserted Audio CDs in the Finder after iTunes does the CDDB lookup.
[Editor's note: Finally! No more looking at "Audio CD" on the desktop and having to switch to iTunes to remember what CD I was working with! Definitely not a hint, but a nice feature worth mentioning.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020828084041680