The humble CD, originally meant to be just a simple carrier of digital audio on a spiral track, has been finding more and more uses. First as a carrier of data and programs for computers, then as a recordable device. Various ways were found to stuff video onto it (VCD and SVCD) and subsequently the concept was expanded to increase the density of data storage into a system now known as the DVD.
But this use as a blood testing device seems to be in a completely different category.