I've seen these really pretty rainbow effects used on a lot of backgrounds and different banners and I was just wondering, if it's possible, how to make one without using adobe or psp, etc. I've only got gimp and paint.
This is an example I've seen:
example

Do you use gradients or something? Thanks.

Yes, they used a gradient.
U can get the trial for ps or psp.

Yes, it's by using a gradient tool. You should load the gradients onto you're gradient tool because you'll have more choices. In order to do that kind of multi-colored picture. Make a new layer over the picture or whatever it is. Take the gradient tool and make a line across/downwards/any direction. Then, go to the layer palette, and where it says normal, click it and click on color. Viola.

ahem ^ he was wondering how to make it without the programs..

and i dont think you can other than ddownloading the free trials..
photoshop cs [http://www.adobe.com/products/photoshop/main.html]
paint shop pro [http://www.corel.com/servlet/Satellite?pag...d=1047025490241]

You might want to try something like this:
cB ms paint blending tutorial
Instead of using black, use a different color or two. I don't know if it will help, but it's worth a shot.

Thanks for all the help everyone. I'll get back with what worked/didn't.