If you are currently doing a redesign of a color theme (maybe for your website, your blog, a banner for your design project, or whatever), you’ll probably appreciate this page at Design Media website.
It has easy to use sliders that will help you to find color matches for your new design and of course, the hexadecimals of the "color theme".
The tool also has a pre-defined themes such as Burgundy, Kiwi, Blue Tan, etc if you are not feeling artistic. You can also create your own color scheme and save it. Most importantly, you can export the swatches colors to Adobe Photoshop (.ACT) or Adobe Illustrator (.AI). Whether you are a designer or not, this site will certainly come in handy during a site/blog/logo/banner/redesign!
If you already have a logo and would like to design a site for the company, you may want to take a look at the online color picking tool. I made a post about it a few months ago here (It’s actually my second post when I started blogging! :))