Just curious, does anyone use GIMP?

I want to try to do some banners and such and I remember seeing GIMP back in the day when Screensavers used to come on Tech TV. For those who don't know, its free and open source alternative to Photoshop and the like.

Well, if you use it, would you care to give me some hints. I'm totally clueless when comes to this type of stuff. Or, if you have any links to some good guides, send them my way, too. I found a few, but they are actually books I have to buy.

Thanks!

GIMP.org
GIMP on Download.com - there's two programs to download and compile

I use it, but I'm not NEARLY proficient. The extent of my use has been making a custom anti-Shiri owned pic.

I'm not too proficient with the GIMP as well, but I do use it.

I can use layers, do some funky stuff with changing colours etc.. but not even nearly the kind of stuff that Fain can do with whatever he uses.