When you are working with your VMs don't you hate how they seem to just keep getting bigger and bigger.. especially when you are not installing extra software. This always bothers me and I am always looking for ways to make my VMs smaller.. I've written scripts, used the windows system cleaner (cleanmgr ) and run 3rd party tools and I just manage to reclaim a few more bytes.
Recently I found "System Ninja" from "Singular Labs" which is a free tool for cleaning up "Junk" files from your computer. I know what you are thinking.. with a cute name like "System Ninja" it probably installs spyware and then crashes your system, but if you can look past the kitschy name, it's an awesome tool and it will save you heaps of space!
I have run this on a number of my VMs both at home and at work and on each occasion it has found tremendous amounts of "junk" that I have happily removed from my VM without any negative impacts.
This screen shot is a typical example where System Ninja has found over 6GB. After removing this junk from my VM everything still worked as expected but my VM was a LOT smaller!
I am finding System Ninja typically finds between 2GB and 6GB on the various systems I have been testing.