There is the luggage that you pick up and think, "My God...how can it be this heavy when it's completely empty? By the time I've thrown a couple of t-shirts and a toothbrush into its murky depths I won't be able to lift the darned thing."
Then there are the bags that are deceptively light in the store yet, once packed, transform into unwieldy clunkers that require a week's worth of pre-trip exercise to enable you to lug them around.
Then there are the too good to be true...I bet Tinkerbell had a bag this light when she flitted around with Peter Pan...variety...like the bag below which tips the scale at a mere 135g.
Something that seems like a dubious claim until you realize that they are made of that brand of flashspun high-density polyethylene fibers that we all know and love...Tyvek. All the Tyvek-y pros are there...the bags are waterproof, tearproof, and 100% recyclable...and the cons (a passing resemblance to an extremely large Air Mail envelope) have been mitigated by the shiny, silkscreen printed, colors. A rare mix of the durable, the practical, and the aesthetically pleasing...