Among the many, many stories I've recently written for firstname.lastname@example.org recently is one about changing dates of the UK mushroom season. There's been a huge effect in response to warming — the autumn season is twice as long, and some mushrooms are popping up in spring, as well as autumn.
This is a lovely example of you-never-know-when-it'll-come-in-handy data collection. The data — ranging from 1950-2005 — were collected by Edward Gange, stonemason by day and fungal recorder for the Wiltshire Natural History Society in his spare time. The lead author on the paper is his son, ecologist Alan Gange. Isn't that nice?
Another good thing about this piece is that it gave me a gave me a chance to interview Andy Overall, one of whose fungus forays I attended last year.
Back in the dim'n'distant, I had a lot of fun writing a longer piece for Nature about ecologists using data collected by amateurs to measure the effects of climate change on living things. If you ask me, this is probably the most important ever non-specialist contribution to science. Always glad to hear of any other candidates, though.