Compressed mds files?

I’m new to alcohol, and I’m not even sure that it’s the program that I want it to be. Basically, I want to be able to create really really small mds files, in this case of Psychonauts. (Just 'cause I have a 200GB hdd, doesn’t mean I want to waste space.)
I remember wanting a no-cd fix for the sims 2, and finding one on megagames that consisted of an mds file which was only 1.54 MB. This file is an image of the whole play disc. I want to know how to do that. Alcohol is probably entirely the wrong program, knowing my luck.

Thanks for any help.

Edit: to prove my point, the file I mention is here. It’s in a zip file within a zip file, and it’s only 158KB. Download it if you don’t believe me. :smiley: