Suaoki Air Compressor, $19 with code 835UAXSZ

While it’s certainly not as fast as the quarter-operated air compressor at a gas station, this glove box-sized compressor can save your bacon if you have to change a tire, or just can’t be bothered to find change. One reviewer describes it as slighlty larger than two decks of playing cards, so you shouldn’t have any trouble finding somewhere to hide it.