Ok, this is a tutorial on how to make awesome looking abstract things with GIMP 2.6.
First start by making a separate layer, and in that layer a radial gradient, from whatever color you want to black.
Then go to Filters>Distorts>Whirl and Pinch and adjust the whirl angle to be whatever you want it to be. I suggest a high number. You don’t need to change the pinch and radius, but you could experiment.
Then go to Filters>Distorts>Waves and play around with those variables.
Then duplicate that layer and change the mode to addition or hard light.
After that if you want a different color go to Colors>Hue saturation to make it whatever color you want. Also feel free to twirl it a little more and to use that wave filter a little more. Another thing you could do to increase the awesomeness is go to Light and Shadow>Supernova and make it a seperate color and then whirl and pinch and wave as wanted to. Another thing you could do is go to the pen tool thingy and make a path, then stroke it, distort it, and wave it. Just make anything, then twirl it, and use the wave filter thing.
Pretty much just repeat every step above and experiment with colors and numbers!
Btw, sorry for not having screen shots…