A number of manufacturers make field sensor networks that use protocols other than WirelessHART or ISA100.11a and in fact have been on the market for a number of years and in a wide range of form factors.
Every so often, a press release just catches me. This one reached out and grabbed me...I had to read it. It sounded like a science fiction story. Well, the reality wasn't what I had hoped, but it is pretty cool, nonetheless.