Arch Linux

We've been running the Belgian Arch Linux mirror at work for quite some time already, but even though some of my colleagues run it as their main Desktop OS, I could never be bothered to try it out.
A couple of weeks ago, a coworker at a customer seemed really enthusiastic about it, so I thought I'd give it a whirl myself.

The main idea behind Arch, is to provide a distribution which keeps things as simple as possible. A good example, is the way they replace the classic sysv init system with a simple array of values. No upstart, no systemd, no tools necessary to create start/stop symlinks. The order in which you place the names of the init scripts, is the order in which they are started. Simple, no?

Arch Linux is a distribution which performs "rolling updates". Unlike Debian or CentOS, you don't have "version X" installed. If you choose to regularly update your packages, you're always running the last available version. This gives you a cutting-edge operating system, which might not always be suitable for server use, but is definitely cool for a desktop machine.
Building your desktop environment is similar to Gentoo or a minimal Debian install. After the install is finished, you end up with nothing but a command-line, and it's up to you to choose a Desktop environment, install your applications one by one, and manually enable each and every feature that you want. This is a lot of work, but luckily Arch has an awesome wiki, with tons of information on how to get stuff working.
Pacman, the Arch package manager is great as well. If you've ever complained about yum being slow compared to apt, prepare to be amazed by pacman.

Running Arch Linux as your main desktop is OS won't be the easiest road to take, but it's definitely one of the coolest.