ColorWasher is the only auto-color tool I've tried that made it into my photo-correction tool kit. It is also one of the few that provides for a lot of manual tweaking of the results. Version 2 was just released, and there's a demo version available.

http://thepluginsite.com/products/photowiz/colorwasher/

Andrew:

Can you give some examples of what you feel it does better than Photoshop, from the perspectives of ease of use and/or quality? Does it simply replace the Photoshop auto-color function or do you use it for other purposes?

Have to agree with Danny on this one Andrew, can't see anything there that can't be done with standard photoshop tools. Would be happy to know why you think it's so good, maybe I'm missing something.

I wasn't all that impressed with ColorWasher until I started hitting some images where it gave me better color. For example, it gave me better color in the Spider Flower photoart I posted here some time ago. I also used it for the saturation boost in the Smiling Eyes photoart, because it gave a better result than Photoshop. But at the same time, I also have photos where Curves did better.

So all I can say is I've found it of value. But not right away. So my suggestion is to leave the demo loaded and just give it a shot when you find yourself struggling to do a correction with native tools. And if it ends up being of no value to you, then just give it a pass.