I like to build VMs for any customer projects I’m working on so the OS and environment will match theirs. That means I have between 8 - 10 VMs on my machine at any one time and with 500GB of disk I have to be careful of space. My usual size for a Windows 7 or Windows 8 VM is 30 - 40GB since they usually contain only the OS and some administrative tools like Putty, Winscp, Domino Administrator, Jexplorer, Softerra’s LDAP browser etc. Windows itself eats up more and more space and I found on one 30GB drive today that the winsxs directory was 12GB. After doing some research (surely I could clear up some space there?) I ended up running the following command from an administrator run command window
dism /online /cleanup-image /spsuperseded /hidesp
which removed the SP1 one files and cleared up nearly 4GB of space. Add to that clearing out the Temp directory and the Downloads directory and I free up nearly 9GB in total.