FRETS.COM
Shop Tip #362
© Frank Ford 2006; Photo by FF

That's right - it's the world's most popular rolling paper and it's a traditional companion in many a machine shop.  Exactly one-thousandth of an inch thick, the cigarette paper is a quick reliable lightweight shim and "feeler" gauge.  While you're thinking about it, why not measure your business card and credit card to have a couple more handy gauges?