The VM placement algorithm inside Entropy is no longer a child and it deserves its own name now: Btrplace.
To celebrate this announcement, I have developed a sandbox that allows users to play with the algorithm on a simulated datacenter directly from the browser. It's simple, it's fun and it is available here.
This sandbox has been realized in the context of the FUI openCloudware project. This project aims at building an open software engineering platform for the collaborative development and deployment of distributed applications.