I just wanted to run MogoDB in a VM.
If do too, just make sure you've got Vagrant and VirtualBox installed. I used Vagrant 1.9.1 and VirtualBox 5.0.30, but other versions will likely work.
Then, checkout or download this repo somewhere, cd into that directory, and then vagrant up
If you want to follow along with how I got to this point (perhaps you're reading this in the future, and it no longer works), I tried to document the steps I took and the challenges I encountered. Good luck, and happy hacking.