Not gonna lie, I often have a hard time picking out a complimentary, engaging color palette for sites (see my obsession with Brown + Orange and now Grey + Pink) and often don't love the over complexity of Adobe's Color Wheel Picker. Fortunately, Coolors seems to ease my pain a bit by creating a very simple interface for generating palettes. Look at this one - I'm totally going to snag that for yewknee.com version 10.

Long story short, it's handy and it's simple, a combination that almost always wins my heart.