You can see Particles addon

This is a Small Test (not the Mod : Sortal) you can play this Test on Portal.

You Opening the .rar File and go to SortalTestMaps and you can see Materials,Sounds,Scripts and more
this folder´s copy and paste to this Steam\SteamApps\SteamName\portal\portal.

and go to Portal and write in your Console Map SortalTestMaps.

and have Small Fun :D