Billed as being "perfect for boats, parties and restaurants," Edmund Scientifics' The Incredible Spill Not is simply a 13-buck gizmo that combines a flexible strap with a rigid arm and base. While at first it may seem somewhat silly...
...you can't deny that this thing would be useful on a boat:
As an ex-waiter though, I can't see restaurants getting behind the device, unless they make one that can hold four cups at once. And never mind relatively stable, straight-walled coffee mugs; you wanna impress me, make one that can handle martini glasses. In terms of ease-of-spilling, those are by far the worst glassware to handle on a tray.