This could be a known trick.

I was looking for a way to flatten the histogram of the solid noise (Filters/Render/Clouds/Solid Noise), that produces mostly gray tones, so I tried a sine transfer function in Curves. This had the expected result, but also created a nice pattern:



Which got me thinking that if I use different values for X and Y in the solid noise plugin to stretch the noise horizontally, and use a color gradient map on the result, using a medium blue to light blue gradient, I could feel the urge to take a dive:

yeah, that was something i messed around when i was new to this board:
viewtopic.php?f=11&t=5082

Thanks for the tricks, ofnuts
Wow, ton's of addition info on your link, Esper.

yeah we have something for you all,,, all time ennjoyment