I've used "reflectix"tm Al-coated bubble wrap for a lot of camera cases – but with a silnylon liner (as well as a silnylon shell for moisture protection), as the aluminum layer will SCRATCH LCD display screens on cameras etc.
The stuff also makes a great "thermos" box for keeping food hot while re-hydrating and insulating your hands from the hot food bag. – just use packing tap to assemble and bits of hook and loop for a latch.
Also makes a great light insulator for water bottles too.