These 2 WAV files (Windows PCM and normal formats) are the Apple Pippin Boot Sound that you can use in older versions of Basilisk II or SheepShaver.

Mac destop pictures/tiles from classic OS'S in PNG format for any modern OS See also: Additional Mac OS desktop patterns and pictures  

Psych is a nice demo with a chiptune playing in the background.    

Vanlandingham is the Macintosh's answer to the Amiga's "boing!" demo.  When you launch the app, it will take 20 to 40 seconds for the animation to start, depending on your hardware, since the program draws at high resolution...