Arch-based distros that are actually pushing Linux forward.
If you're looking for a distribution for an aging machine and you want to go with something other than a Ubuntu-based distribution, walk through the Arch with Omega.
BunsenLabs Carbon is a mishmash of Linux desktop components, which shines through when you go to customize the desktop.
Whether you want to run a simple desktop or host your own servers, check out these Debian spin-offs first.