I have been using a Lenovo T60p computer with Windows Vista since I joined Microsoft last year.  Lenovo has a great System update utility that keeps the service packs and applets up to date.  Recently the update utility installed a new version of the Power Manager application - this one has a much cooler interface - all possible with WPF.  After playing around with the new interface, it looks like they spent the time to make an easy-to-use and visually appealing interface that resizes appropriately and responds quickly.

Great job Lenovo!

Lenovo Power Manager Power Use Tab

Lenovo Power Manager Battery Tab