I spend a lot of my day designing Metro stuff for Windows Phone. And the majority of that time is spent creating mockups of each area of whatever app I am doing, along with testing it with each accent color.
Embarrassingly however, every few days I head over to Bing and search for the accent colors. I've gotten so used to this that I forgot how silly it is.
I almost hit myself tonight when I saw this really simple, but awesome little swatch file for Photoshop that I should have made for myself months ago. So if you're a designer, or a dev that does design, or have PS installed for no conceivable reason at all, head over to the source and download and run the swatch file.