An opinionated LXC wrapper.
LXC, aka Linux Containers. In case you don't know what they are, it's basically virtual machines without emulating the hardware. In technical details, it's chroot on steroids, because the filesystem, processes and networking are separated from the host. More information here.
This technology is getting a lot of traction since ~2 years, because it allows people to create isolated environments very quickly, very cheaply. Fedora 21, for example, will have each application run in a different container. Deploying containers on AWS lets you build multi-tier architectures for cheap, etc etc. There are many applications.
I personally use them as "VMs" for my projects (each project gets a VM). And lxc-wrapper is there to help me with that. I think this is a common usage though, so I thought it was worth sharing.