I have an old PowerBook (from about 2005, not long before Apple's intel switch) that still runs fine, after replacing RAM a couple times. I use it as my back-up computer at the office to this day, sometimes bring it to the coffee shop to outhip the hipsters. It's been running the Debian PPC port for many years without much trouble.
Of course this does not come as a big surprise; I'll just keep running the most recent version until the hard drive dies and my current laptop becomes the back-up.
Are there any distros still standing with PPC support? I used to run Ubuntu, but it was dropped years ago.