They go nicely with over 1800 URL sites I found using the phrase
"spontaneous human combustion".
On the page Rick cited I was amused by the confident ordering of paper >
cotton > wood. I also snickered at the listing of highly reactive
substances with no mention of surface state or history. Are they really
talking about aluminum, or some oxide on the aluminum surface? And was the
glass recently washed in acid, or alkali, or what? If you know anything
about contact electrification, you know such things make a huge difference.