As Tony/ful-rac said... "I believe he's talking about a bait cage suspender, and no they are not new. They clip to the outer ring, so no matter how the middle ring lands, the bait cage is always centered."
The bait suspender idea isn't new...the concept has been around for a while especially with some of the 'deep' home-made flat nets from San Diego Bay. The Promar Bait Suspender was designed for the 32" classic style flat net. It was not designed to be used with the conical style nets.
Here is a short video showing the bait suspender catching crab on a 36" Promar flat net.
http://www.youtube.com/watch?v=E1QJRB9nv6w
Jim / Saba Slayer