A few years ago a friend moved from one apartment to another a few miles away in Copenhagen by herself over two days using a rented Christiania cargo bike for transportation. These have been around since the 70s and have a reputation for being very reliable transport. Close to ideal for moving loads up to about 3 or 4 miles in traffic calmed urban or suburban areas.
A few people have brought samples to the US, but now an importer exists and a dealere network where you can get sales and service is growing. I've seen a few in the West Village in Manhattan recently and suspect they are from one of the dealers there.
Here is a report from somone who visited BoxCycles - the importer near Boston. If you are interested you may want to check out the BoxCycle blog. The last time I checked these go for about $2,700 in the US - about the price of 700 gallons of gasoline.