Now for my Great Idea: a device that uses the air in your bike tyres to fill up your air mattress
Mmmm, Dave, you might want to check first with those who used to drive VW beetles which used the air in the spare tire to power (if "power" in the word I want--maybe just "operate"?) the windshield washer system. Seemed reasonable enough: tube atop valve uses the spare's air pressure to pressurize the reservoir, thus forcing the liquid onto the screen when the driver turned the knob. Um, yes, so long as the spare was primed.
I learned about the limits of the system the hard way, crossing the Burlington Beach Skyway late one wet-n-snowy December evening in the mid-70's, returning to Toronto from NY in Marcia's '68 1200 Beetle (in most other respects an exemplary vehicle -- our Italian mechanic used to say, "That year, they got everything right.") Not the place where you want to find you have an uncleanable windshield...I made it across, found a gas station, opened the hood; and I have to say, it never even occurred to me to look at the spare tire. Silly me, I thought the problem was no fluid in the reservoir.
So (he said, retrieving the "sleeping pads" thread, but only just) maybe reusable/refillable/recyclable emergency CO
2 cartridges for knackered cyclists filling their pads at the end of the day?
Cheers, John