Can't find a tutorial.. please help!

Hi all. This is my first post here. A while back I was reading a tutorial on different types of retro effects you can create with Photoshop. One of the effects is like the one I used in the background of this icon:



I cannot for the life of me find this in the memories. I'm pretty sure it was here that I saw it. Does anyone know what I'm talking about, and could you point me in the right direction?? Thanks so much!