The Brouhaha Bicycle Trailer is a zero towing force trailer for your bike. Its electric motor goes when you go and brakes when you brake, resulting in virtually no extra effort on the part of the cyclist. Best of all, it can be modified to fit nearly any need. If you can haul it with your car, you can tow it with your bike and the Brouhaha.
(BTW, this isn’t about free rides. You’re still pedaling your bicycle, but you’ll be able to keep up with the other bikes while hauling a couch!)