From their Homepage:
BunsenLabs Linux is a distribution offering a light-weight and easily customizable Openbox desktop. The current release is Deuterium, derived from Debian Jessie. The project is a community continuation of CrunchBang Linux.
This distro is awesome. My favorite Debian Stable based distro, with an amazing community. It is extremely lightweight and runs blazingly fast even on old hardware. And it is full featured and user-friendly enough that I use it on even the latest hardware.
Image Credit: Screenshot by Omar Cheng