Palette Selection

[whipstache]

Cool beans! I've gathered a bunch of colors I like and will use your trick on them now.
You make a palette file? Why not save a palette in GIMP or, assuming its possible, in Photoshop? I usually pass any graphics I make through GIMP at some point to add color to them unless I'm banging out a 5-min quicky in Inkscape. Maybe I shouldn't do that either?

I find it's easier to open a new tab in photoshop and just blob the colors I'm using there, rather than take the time to add them into any of the actual frames. Just my preference. When I need to switch colors, I just hop over the the palette tab with my eyedropper tool and grab the one I need. Plus, doing it this way allows me to play with them until I get exactly what I want while being certain not to have any impact on the graphic (or in this case, map) that I'm working on.

But, as I said, it's just personal preference.

[Chick]

Photoshop has a color swatch window. I just save each color I'm using as a swatch and keep that little tool window open. One click gives me whatever color I need. When I'm finished, I can save that set of color swatches as a file and delete them, so if I ever revisit that map, I can also reload the colors.

[Azélor]

For cartographic purposes, you could use color brewer v2 http://colorbrewer2.org/