Aerless Vacuum-sealing travel packing bags
This vacuum kit works with any bag you already have, giving you more space, better organization, and less travel stress. I have a set and have been impressed with the compression -- especially for sneakers of all things (since you can never really smush them together fully, except in these bags). The vacuum piece is small and (usb) rechargeable and the bags themselves are waterproof (and therefore stink-proof should that be a consideration).
Plus, to be honest, it's just kind of fun sucking all the air out of something.
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