After breaking a series of coatracks, a Virginia-based tinkerer who goes by the handle Whamodyne needed to make some stronger wall hooks to hang his heavy winter gear from. His mounting solution was to use lag screws driven into wall studs, but he still needed a form factor for the protruding end. Whamodyne's solution: Concrete light bulbs.
By hollowing out a cheapie light bulb, filling it with mortar mix concrete and breaking the glass off, Whamodyne was able to create some seriously heavy-duty hooks with enough bulbousness to hang a heavy coat without having to fumble with hanging loops and hooks. Having perfected the process, he's posted an Instructable of how to do it.
Want one, but don't feel like getting your hands dirty? He also sells them on Etsy.