Nestled at the back of Tyler Brûlé's wonderful Monocle magazine is an advert for their range of bags, co-produced with Porter of Japan.
Here is what the website says:
This bag is small enough to meet all hand-luggage regulations - it will easily fit into an overhead cabin or under an A320 seat - yet, with a bit of smart packing, could contain enough to last you a week or more. Also, includes a laundry bag, a pouch for toiletries and pouch to store a bag when you get back to your pied-a-terre. L50xW42xH30cm.
Let us see how it (and I) do on an 8 day trip to London, Paris, London and back again to New York.
As well as a week's supply of clothing and 'stuff', I somehow managed to squeeze in my Apple MacBook Pro, a Nikon D80 Digital SLR, the current issue of Wired and Bill Bryson's 'A Walk in the Woods'.