As I am working on the December Blog Train and trying to stay true to the color palette, I find that I need to sample from the color palette and then quickly apply to my .psd. Here's an easy way to do that:
From Planet Photoshop: You can use the Eyedropper tool to pick colors from any area of your screen. First, press the letter I to select the Eyedropper tool, then click-and-hold inside your document, and drag outside the document window onto the object you’d like to sample. Release your mouse button and the sampled color appears as your new Foreground color. [This post is from 2008, and I think that since then it's been improved so that you can actually sample from anything on your screen, not just image docs.]
thanx
that makes it possible to have the palette outside photoshop and making it a lot more easier to pick up colors 
I recently used a swatch file for Photoshop (.ACO) and it's another little thing that will probably change my life. I'll probably make a more detailed post about it when I get a chance.
Useful stuff. Thanks so much for posting!
I had no idea you could do that!! Here I'd either been pasting saved palette images into my documents, or using the print-screen button on my keyboard to get a screen capture, which I paste into my photoshop file. lol.
Confirmed that it does, in fact, work with absolutely anything visible on your screen, using CS6+Windows 8 (beta, but probably acts the same as Windows 7 or 8 ). oh that's so cool.
I am going to have to try this, thanks
This one's new to me... nice tip!
Thanks for the tip. I must try. I too have been doing the print screen route.