About ATC's

I was thinkin' that if i'm gonna have a blog displaying ATC's that maybe I had better give more information about these little works of art in more detail. When I say 'works of art', I'm not necessarily speaking of mine. Yet, I'm also not saying that I don't think that mine are good. Sooo... I googled under "ATC's" and oh my, is there alot on ATC's. So, instead of writing about it here I thought that I'd put a few links on my side bar for anyone interested. Why do all that work when it has already been done?:)