So, this idea comes from the thought back to cyberwarfare. I remember having the custom map skins and model skins. Well one thing I'd like to do with one of my maps (without having the skins stick to SF until I close out the game) is the ability to use custom skins for certain maps to make the blocks not look retarted and stand out with the layout...
Something like info_blockskin_red, info_blockskin_blue, info_blockskin_neutral or something like that
Each one would have several options that direct to vtf's and it automatically creates a temporary .vmt for each model/texture used by the blocks. You can have options for base textures, lod's, normal maps, and whatever else is used for the destructability of the blocks. This will allow you to load vtf's into the .bsp and run it straight from there too
From a mapping point of view, it lets you add some special skins for special maps (like a pepsi vs coke map using those skins on the forums) and different stuff like that. It allows you to load it into client's computers without actually forcing a permenant skin download