I use
Color Schemer a lot. People come up with schemes, and I'll download the latest. Always gives me great ideas for colors. The website shows some of the latest pallets, so you get an idea what I mean.
Sometimes, I match the sponsor site. A lot of times, I match the template that has graphical text I'm too lazy to put new background color on, and use that color.
I get really bored making sites all the same color, so I try to at least vary somewhat. I do use pastel backgrounds more than bright colors, and use bright colors, or high contrast colors, for sponsor links.