You want proof there's a Linux distribution for absolutely every possible application? Here's one for you: Hikarunix, a distro dedicated to Go players and based on the ever-versatile Damn Small Linux (DSL).

Go, in this case, is not the very funny 1999 movie, but the Asian strategy game. It's vaguely similar to checkers or Othello, over 4,000 years old, and is said to be a whole order of magnitude more difficult than chess. (The line I've used to describe it is, "Chess is one battle. Go is the whole war.") I play the game intermittently, and I'm bad enough that I get consistently whomped by just the computer, never mind the human players. (The "Hikaru" part of Hikarunix is a reference to Hikaru no Go, a manga / anime series with a small but deeply enthusiastic following about a young Go player and his rise to mastery.)

Hikarunix is a great example of how a whole Linux distribution can be packaged and presented as a kind of mega-application -- one that doesn't need to be installed per se since you can run it as virtual machine in Virtual PC, VMware or VirtualBox.

Boot the Hikarunix image and you'll be taken to a desktop that sports quick links to many Go tutorials, practice programs, applications that let you play against other people across a network, and the usual package of apps included with a DSL distro (Firefox, Sylpheed e-mail, etc.). It's addictive -- much like the game itself, which you can learn the basics of in about five minutes and spend the rest of your life getting trounced at.

One caveat: Installing the Hikarunix distribution to a hard drive is a little less straightforward than it might be with some other distros I've played with (including the vanilla edition of DSL). This is a little problematic if you want to install it somewhere and then update it regularly, but not fatal.