I just bought one of these CrossRacks from a different folding bike company for my Bike Friday - Xootr. http://www.xootr.com/crossrack-bike-rack.html
I haven't used it yet, but it fits fine. It is a single pannier that attaches to the seatpost. I plan on using it for light 'credit card' touring when you only need some clothes and no camping equipment. It would work for bread and milk. It seems to be more out of the way than the usual panniers and racks. Front bags don't fit very well on my Bike Friday because the cables are in the way.

CrossRack Bike Rack Features
Mounts to most bicycles and scooters.
Centers load for best balance.
Positions cargo in slipstream of rider for low drag.
Works with most standard bicycle panniers.
Detaches in 5 seconds via locking pin.
Rack "horns"can hang many standard bags, including plastic shopping bags.
Welded aluminum construction.
Fits post diameters from 1.0 - 1.4 inches (25 - 35 mm).
Weighs 664 grams.
Load limit: 25lbs.