Cubic Gate: Another small cubic device, this item is fashioned from carnelian. The 6 sides of the cube are each keyed to a plane, 1 of which will always be the Prime Material, of course. The other 5 can be chosen by any means desired. If the side of the cubic gate is pressed but once, it opens a nexus to the appropriate plane, and there is a 10% chance per turn that something will come through it looking for food, fun, and/or trouble. If the side is pressed twice, the creature so doing, along with all creatures in a 5' radius will be drawn through the nexus to the other plane. It is impossible to open more than 1 nexial point at once.How is it that I only just realized that this is a direct borrowing from De Camp and Pratt's The Carnelian Cube? It's not like Gygax was even hiding the fact, since he outright states the material from which it's made in the very first sentence of the item's description! Shows how closely I must have read that description in years gone by.
(It's worth noting, by the way, that both D&D III and Pathfinder have retained the De Camp/Pratt connection in their descriptions of this item. Does anyone know if the latest incarnation of D&D does the same?)