You bet, according to Robert Hansen, CEO of SecTheory: Just tweak your Web browser so it doesn't run a lot of flashy Web graphics.

In an admittedly , Hansen took a look at the 100 most popular sites on the Web to see which ones burned the most power on his laptop. The winner? MySpace.com, followed closely by Gamespot.com.

The sites that consumed the most power tended to use JavaScript or Adobe Flash animation, often cycling through a series of graphics over and over again. "Those technologies just were hogging all the resources on the computer," he said. "Flash banners actually seem to be the worst," he added.

The computer's CPU needs more power in order to draw the moving images created by the Web site, Hansen explained.

Even sites that appear static can sometimes quietly draw more power than expected. 's Hot News Headlines banner, for example, uses up CPU power every time a new headline is generated, Hansen said.