Haha! Interesting, it seems we had the exact same line of thought! Palette maker started with the idea that a gradient could be either a "rainbow gradient" going throught all the hues at full saturation(blue, green, yellow) or a "straight gradient" (blue, gray, yellow). It's interesting with your discovery that PS uses a LAB gradient, I thought it used the "straight" method. I guess that since the LAB goes for the middle it turns out the same as the straight if you use complementary colours.
Here's an MSN upload for those of you having troubles, enjoy:
http://cid-5762070d2575b6b4.office.live.com/self.aspx/.Public/Palette%20Maker.zipI'm glad many people say they can use this!
Please, if you have used it for anything you think turned out good, show me!
I could propably create an export function for the PC, but all PC:s to my knowledge have print screen. For the mac I wouldn't even know where to begin