Is this possible?
My hard drive is low on disc space, and this would be really nice.
Also, as a side request, mounting for Portal : First Slice - http://www.steampowered.com/nvidia/ . It contains all portal props/materials/sounds/entities/effect and a few of the early levels. You CAN just extract the contents and get the portal spawnlist from the gmod GCF, but this is a pain and takes a lot of hard-drive space.