Like Bike Hugger points out, the Travoy looks a lot like the handtrucks and golf bags we’ve seen people pull on their bikes. The Travoy takes that idea a step up by making it foldable and collapsible so you can use it like a backpack or pull it along like rolling luggage.
Unlike other bike trailers, Burley’s 10 lb “Urban Trailer System” is still useful independent of the bike. Attached to the bike via a seatpost hitch, the Travoy can tote 60 pounds of stuff from market to home.
More at Burley Travoy product page.