Do you use iGoogle? I do, and I loved when they added the themes that change during the course of the day. But it always bothered me that the page was devoid of any real color where the gadgets reside. So I made myself a gadget to add colors for both the page background and the gadgets themselves (basically color everything the iGoogle themes do not), and then made it flexible enough that you can either select colors from a dropdown menu or specify your own custom colors via hexadecimal values so you can truly make your page whatever color you want. Since no additional images are loaded, you won't get any slowdown in page load time. And it will work with iGoogle skins so you can still get the time of day or weather changes that Google offers in their themes.

Notice the bottom half of the picture has a Deep Blue background color with a Light Blue gadget color (click to enlarge)

To add the gadget, click here. When you add the gadget, click OK to give permission for the gadget to be inlined, so it can modify the page's colors. Then click on the down arrow in the gadget and choose "Edit settings" to get access to the color preferences.

If you use multiple tabs, you can actually add the gadget to each tab to create different color schemes. Just make sure to pick the right "Tab Number" under the settings to color in the correct tab.

Closeup of the gadget and its color effect

Let me know what you think and if you have any questions in the comments here.