iGoogle

If the Google personalized homepage wasn't already great with the personalized content and the tabs and sticky notes that you can access from anywhere, google has now even put up themes for your homepages. I've chosen a Seasonal theme where after entering my current location, it will keep changing the picture, including the position of the sun and moon, and the seasons! And if just the sheer coolness of it wasn't enough, it looks great as well. i(love)Google!