If something was to happen while aboard your pontoon or motorboat that involved an immediate evacuation, the Extendable Lifeboat would be such a useful item to have available -- to say the least. One life jacket per person might be the law, but that temporary solution isn't ideal if rescuers are an uncomfortable distance away.
Haimo Bao entered this concept into the 2012 iF Design Talents. It is an innovative self-inflating vessel that can be compactly stored within the bow of your watercraft or tucked to the side of a wider deck. A generously sized air inlet causes the life raft to expand lengthwise, creating the space to fit two passengers within its cushioned gunnels. From the illustrations of the Extendable Lifeboat, it appears as though an additional child or two might fit if need be.