I have a couple of these as well, one cardridge even with the original box, but both (while outwardly in good shape) are in poor shape inside. I think only one of them will actually crank, and possibly only backwards.

It's possible (though probably fairly expensive) to get hold of these in unopened condition, meaning also unplayed condition. The film stock itself may still be deteriorated from the effects of time, but at least it wouldn't be damaged by the mechanism of the cartridge.

I guess the real question would be whether or not it's worth it to break open a new cartridge to scan the film. If there was actually any alternate footage at all (though I'm pretty sure there isn't), it would definitely be worth it. Regardless, I'd love to see some kind of preservation happen since this was really the only moving Star Wars footage I got to see besides the Holiday Special until Star Wars finally came out on video.

For the record, here are are the cartridges that were available for the Movie Viewer:

- May The Force Be With You (came with the viewer by default)
- Assault on Death Star
- Battle in Hyperspace
- Danger at the Cantina
- Destroy Death Star

--SKot