This small black pot has a removable lid and an iron handle. If the pot is filled with water and some decaying organic matter (a dead rat, a severed hand, or something of similar size) within 24 hours a patch of Green slime grows there.
Book of Vile Darkness 3.5 By Monte Cook
By carefully dumping out the contents of the pot (a standard action), the slime pot’s owner can place the patch of slime where she wants it. She has no special control over or immunity to the slime, however.