A coffee machine that only accepts branded/DRM’d coffee capsules.
Via NFC maybe? It could also be mechanically or via colors or patterns. Something we looked at at Anoto during 2008, to identify (rather than protecting) different types and colors of whiteboard pens.
“In Keurig’s case, it’s less likely that the company is trying to lock coffee competitors out than bring them under control. … the company already said it plans to issue licenses to third parties so they will still be able to get their product on Keurig machines for a price.”
This would be very similar to Apple’s approach towards peripheral manufacturers.