Get a notification when your battery is draining and virtualbox VMs are running.
Maybe you have a few VMs running on your laptop (perhaps started by vagrant) and someone calls you to a meeting. You take your laptop with you to show something or keep notes. Half an hour into the meeting your laptop complains that battery is critical. Yep, you once again forgot all those VMs in a running state. Now find an excuse to go get your charger and plug in. Or use this small program and never forget again.
Windows, Virtualbox 5 COM library, .net Framework 4
Freeware
I made this for myself. If it works for someone else that's great. If it doesn't write an issue and I may be able to help figure it out. But don't count on that.