Some web frameworks are basing on using PNG images as backgrounds. Some of them are simply 1xN pixespixel PNGs with single color, others contain gradient (going from color X to Y).
For example, I'd like to generate 1x100 pixel PNG with color #666666, or 1x100 pixel PNG with gradient starting from #999999 ending with #666666.
Is there a Windows tool specialized in such things, or in which generating such image is relatively easy (doesn't require manually creating new canvas, choosing color tool, filling it etc.)?