Linux will eat itself
When I came across Distro of the Month I started thinking that maybe there’s a problem with the number of Linux distributions.
Distrowatch.com tracks approximately 372 different Linux distributions. At one per month, it would take 31 years to make it through the list – assuming that no new distributions arrive during that time, which I’m afraid is wishful thinking.
Distrowatch’s How Independent Is Your Distribution page boils the numbers down some – 129 of those 372 are based on Debian, for instance. Even so, you’ve got four or five years of work ahead of you there if you just want to sample the major families plus independent distributions like Puppy Linux.