I've been playing a bit with Docker and found I couldn't get the kernel option to work (the linux-aufs_friendly kernel just wouldn't work on my Arch setup). However, that forced me to the option of using vagrant to set up a vm with docker configured and I found that great - I recommend this option over playing with your kernel.<p>I'm a long time virtualbox user but had never played with headless vms and never realized how easy that is with vagrant. Additionally, using vagrant to get a coreos vm running, with docker all set up, was pretty cool. So far I'm finding the payload of the vms rather heavy (with the os overhead), but I haven't really got down to setting up individual docker app containers. I'm looking forward to that, and even more to what could lie ahead for this space: vagrant, coreos, docker, chef/puppet all look to making a very promising convergence.