But it’s not so often we see it used as an integral component for a property other than its stickiness, so [DusteD]’s reaction timer project is interesting for having hot glue as a translucent light guide and diffuser for its LED seven-segment display. The hot glue fills the enclosures behind each segment, and after several experiments it was found that the best filling method was from behind against a piece of Kapton tape. We’ve seen a different take on a hot glue light pipe display before.