Looking for a bag (up to 4 of them as 4 of us are travelling) to take as hand luggage on a flight. Needs to be as big as possible within the limitations of the hand luggage (max 55cm x 40cm x 20cm), but at the same time as light as possible - max of about 400g, but lighter would be better as we're flying with Thomson and they only allow 5kg.
Will consider any style of bag - rucksack, tote, hold-all, trolley case or even just some sort of decent quality carrier bag (I considered taking those tartan bags that grannies take to the launderette but my friend said she'd disown us at the airport!), the lighter the better, and any more unusual ideas also considered.
Please include price inc cheapest delivery and either a photo or a link to something similar initially.