My primary laptop is somewhere in California being repaired by Apple, so I've been using my previous machine, a Powerbook G3 I bought in 1999. It's running Mac OS 8.6, one of the greatest operating systems of all time.

Yes, there was the initial behavioral adjustment of learning not to look for the Mac OS X Dock at the bottom of the screen to switch applications. That's past now, and I remember why I stuck with 8.6 for years while simply watching everyone else upgrade to later systems and get into trouble.

OS 8.6 was the one that finally got the original Mac foundation right before Apple switched to a UNIX base for OS X. True, UNIX is "industrial strength," as Apple says, but it results in some user-unfriendly anomalies: you have to deal with read/write permissions and root directories. For an individual user, even with sugary UI coatings, this is counterintuitive (although it is the way many operating systems are set up today).

Speed is an issue. The colossal IE 5.1 muddles through Flash and other animation, impeded by a relatively slow processor trying to absorb incoming data at high speed. But that's basically it-- OS 8.6 is rock solid and fun to use. Even when my G4 returns, I'll be keeping this laptop plugged in and on call for some time to come.