The Cartrivision, a 1972 home VCR which preceded VHS and Betamax, contained an ingenious extra: DRM. Or, as Dan at Dan's Data puts it, "Analog Rights Management". It's also a tale of innovation ...

Like the more professionally oriented Sony U-Matic system that preceded it, Cartrivision could fast-forward and rewind tapes. It also had a simple wind-down timer for scheduling recordings.