I found a bunch of old panels with foam shapes glued on them on the N52 loading dock. Not wanting to let them go to waste, I made a nice big box, complete with hinged lid.

I then brought it back to tEp, where I proceeded (all past tense is actually future tense from here on out) to hang it from the ceiling. I mounted a 1 revolution-per-hour motor on the string, so that the box slowly revolved. Since each of the panels are different, by seeing which panel is facing you, you can easily tell what time it is with 15 minute accuracy, and with a little mental geometry, you could probably guess to the minute.