Newton - The niftiest thing Apple has ever produced, IMO. It's the paradigm for the modern PDA and iPhone. Always wanted one, despite the rants.
Twentieth Anniversary Macintosh - Just a simply exquisite design exercise. Have always wanted one since I saw a picture a few years ago.
Hypercard - Probably the best app I've ever used. Easy language, just-about-infinite customizability. Seemingly endless supply of neat things to do. I wish Apple kept up with it, or at least the HyperTalk language.
Mac OS 9 - Super easy to use. I especially like the sound control panel that allows you to play the line in stuff through the output. No equivalent built-in feature for OS X. It also runs HyperCard, and app that should have never died.
iMac G3 and G4 - The most amazing computers of the 20/21st century. They blend style and performance that has never been matched and probably never will be.
PowerMac G3 and G4 - Just for the door-mounted guts. Love it.
iPod nano 1G in white - IMO, best looking iPod, maybe even device, Apple has ever put out. I've had one since the 4 GB was introduced (though I have a 2 GB).
iPod touch - iPhone without the phone. Best move Apple has made in awhile.
That's it for me. And are those in chronological order?
Velocityg4, the Quadra 840av is one of the best looking computers I've ever seen. I'd say it about ties with the iMac G4.