Today in 2004, US Patent 6739087 B2 was issued, an invention of Isaac Weiser and Margaret Weiser, assigned to Exhart Environmental Systems, Inc., for their “Garden Pest Trap.” Here’s the Abstract:

A pest trap for trapping snails, slugs, and the like comprising a base structure and a decorative cover. The base structure comprises a planar surface, a sloping surface surrounding at least part of the planar surface, two or more recesses formed in the planar surface for retaining a liquid for luring the pests, and a containment surface that is inclined and surrounds each recess. The cover rests over the base structure, preferably mounted on one or more side walls that partially enclose the planar surface and optionally have flanged ends for partially enclosing the recesses. Use and maintenance of the trap of the present invention is thereby greatly simplified and may be environmentally friendly utilizing common beer or other non-liquid luring means.