Savestate virtualbox VM on shutdown host

What I'm trying to do is automatically save state the virtualbox VM's on shutdown of my Ubuntu 13.10 host. I always forget that I have multiple VM's open. So when I shutdown my host, the VM's shutdown to (and not in a clean state).

I know that this topic has come up more often but I still haven't found a right solution for this.

My question is if someone has a solution for this? Maybe a script or something (my scripting knowledge is not that good).

Thanks!
Sjosz