SS - What you are most likely seeing are "gadgets", a feature of Windows Sidebar - new with Vista. I suspect the slideshow viewer is an add-on. I've yet to find a way for the default slideshow gadget to access the web for images. It only displays those on the hard-drive.
Gadgets/wikis/etc been around for awhile. Mr. Gates just decided to add his own in the release of Vista.
Is your new client aware of your affinty for SP?