Using Boot2docker for many Docker experiments you quickly run into the size limitation. Here’s how to grow Boot2docker to allow more images.
I’ve created this Gist that explains the steps to take:
Of course you can also just remove (unused) images. There is a simple command to do some housekeeping and remove all untagged images from your Boot2docker host:
docker rmi $( docker images | grep '<none>' | tr -s ' ' | cut -d ' ' -f 3)