List of Mostly Useless Magic Items

[JAL_1138]

Water Clock of Absolute Time - A standard sized and weight water (very large, very heavy) clock that keeps perfect time relative to its native prime material plane. Must be full of water from it native prime plane to operate.

I could see a bunch of these in Sigil next to known gates to various Prime worlds, like how you used to see big clock pillars or walls with three dozen faces at railroad stations.