On: Show HN: Slipshow – A presentation tool not based ...

[dtjohnnymonkey]

When I was in college they would use a transparency projector, but instead of transparency pages, there would be a roll with a crank that you would turn to advanced the roll. You would get the same effect as slipshow.

[DowagerDave → dtjohnnymonkey]

...and if they went too fast the hand smudges and wrapping would make previous content indecipherable when they rolled it back :)