To BSD? Not to BSD.
I thought I was hardcore, and I wanted to try BSD, the better-than-Linux Ur-Open-Source alternative, but I failed. (More accurately, the fact that I have an iMac G5 test machine failed me.)
FreeBSD is the most popular BSD, and therefore lies beneath my consideration. Turns out that FreeBSD does not support this computer anyway, so my elitism was accidentally justified.
NetBSD prides itself on being endlessly portable to a wide variety of processors, and such flexibility appeals to me a lot. In zanier times, I even tried to get a Slackware laptop running with the NetBSD package management, but that configuration was approximately as painful as Gentoo Linux. So I stuck with Slackware on that machine.
Ha ha! Despite running on a wide assortment of pocket watches, NetBSD does not run on this particular PowerPC (i.e., non-Intel) Macintosh. Fine. Everyone says that the truly hardcore only use ...
OpenBSD, noted for impressively oppressive security and for being the only BSD to support this computer! So I have an excuse to use "the difficult one" after all, since the other BSDs can't run on this machine. Grand.
The installation went smoothly enough, although the software mirrors tend to call these machines macppc for installation, but then label all the auxilliarly sofware in the ports system as powerpc. I was pleased how quickly packages installed over the network, and how compact even all of GNOME was.
Oh, except for two gigantic problems: OpenBSD ran slower than OS X (or Debian 5.0), and the fan made horrible noises. Online documentation hinted that OpenBSD developers new about the fan control noise in the G5, but apparently they figured that cranking the fan to the maximum speed was the safest-cum-easiest solution.
Debian it is, then. At least until Slackintosh ships with a 64-bit kernel that supports the JFS file system.