I see... The Airbagged Trailers units are swingarm trailers with airbags. That's pretty basic, makes a lot of sense though because you can keep the swingarm geometry at its best (that's a relative thing) when at ride height, and it doesn't matter when it's lowered. I've thought about something similar for a boat trailer, you'd barely need to back down the ramp to launch. That's simpler and easier to fabricate than my idea though (go figure ).

Found a better picture to satisfy my curiosity: