Technology companies around the world spend millions of dollars on marketing media. Many of these projects rely on real people talking about their own experiences—that staple of corporate video, the talking head.

It’s important to keep asking: what are we selling? I sometimes find it difficult to feel an emotional attachment. Enterprise systems integration or managed hybrid cloud-based solutions don’t always tear at the heartstrings.

But I’ve come to realize that health is the most important product of technology, and that patient stories make the most interesting and compelling talking heads—not corporate executives, engineers, or software designers. Here are four memorable patients