Well, now you can have the same (or almost the same) functionality on PC. The product called Konfobulator, stepped up to the next version after it was bought by Yahoo and got renamed to Yahoo Widgets.
Before it was a very crappy attempt to imitate Apples Dashboard, but the new version is actually pretty decent.
I personally don't use it for a lot of things and out of widgets I have only weather, battery life, wi-fi signal strength and kitchen timer. But it is very nice since it can be called to the forefront by simply clicking one key [f8 by default]. It doesn't really eat a lot of resources either [only 40MB].
Tell me if you found some other cool widgets.