1968: Calendar quirks meant there were a couple of shows on the year's rarest day. Slightly awkward, this, as the performance is from this show but the dancing isn't. Tom Jones, however, conquers all, and without the re-editing we'd never have seen the human Space Invader at 2:10.
1996: You'd kind of imagine David Bowie didn't need gimmicks like that novelty mike stand by 1996, but he had a sci-fi club direction to pursue, dammit. The Pet Shop Boys look on nonplussed, as is their wont.