http://www.merrell.com/US/en/BarefootSaw a pair of those in the store the other day, was rather impressed with the look and feel of them, though I didn't try any on. They sound like what you're looking for.
Friend of ours works at a local sports store that sells these and we had a conversation with her a few months ago on these shoes.
The Merrell Barefoot and similar brands of shoes are marketed toward a very specific consumer who likes the feel of the road/trail beneath their feet And yes, these shoes are compact, very light...and expensive (IMO anyway.)
On the other hand, there are trade offs when considering a shoe like the Barefoot. These trade offs include very little foot support that is okay for light trail or city walking and which does not entail carrying even low to moderately weighted packs and certainly not for people whose feet are not fully conditioned for very thin soled, minimal support shoes.
These trade offs must be taken into serious consideration if you plan to also utilize the shoes as part of your BOB or GHB bag.