Very timely - I'll be installing a smoke alarm in my new workshop! A few years ago I had been danish oiling a jewellery box and, having not used the oil before, was looking up methods etc online at work when I discovered the spontaneous combustion thing. I phoned my wife and told her to go into my workshop, pick up the screwed up bundle on the bench, put it into a tin and place it in the middle of the lawn. She thought I was crazy until I sent her a link to the article I'd been reading!