I gotta say... Great utility!
Now I can have the HD size I want (10 gb) and it only actually takes up the amount of space that is being used.
I used this utility to make a 10GB hd file and then mounted it as slave in PearPC and then used Carbon Copy Cloner to clone my 6GB original image on to this, selected the new HD image as the startup disk in OSX and then made it the master IDE image in pearpc, booted and voila. New more efficient HD image.
"I don't know how to get the lead out!" Ethan (my son), age 13.