Material Editor Tool
A tool that allows you to copy materials directly from the map and apply them to props. It features many options to control the appearance of your material.
Because unlike the default material tool, this tool allows you to use any texture. It also allows you to stretch and translate the material coordinates to fit your needs.
It also automatically applies bumpmaps to your materials, if one is available.
Find it next to the original Material tool, the tool is called "Advanced Material"
You have several options, now.
A.) Find a texture on the map you like, right click with the tool out, and SHABAM, you can start applying it to stuff.
B.) Use the original material tool to select a texture you want in the menu, then open up the console and type:
material_override
and then click the option that pops up, and copy the material path.
The tool menu options are fairly straightforward.
Magnification options control sizing, and translation options will scroll the texture a certain direction.
None that I know of.