In the recent spell of hot weather heres some common sense advise about keeping your cameras safe.
Dont leave your camera in the car boot, first off it's lightly to get stolen but more importantly it gets bloody hot in a car left in the sun, cameras don't like the heat too much, the oil used to lubricate bits can run onto bits it shouldn't be on, the glue holding it together can melt and worst off some circuitsand things can die, cpu chips for example.
(and don't leave you dog in the car either, even with a window open a bit)
Out in the sun. A black camera just soaks up the heat so much the same applies, keep it out of the sun as much as possible.
Some people go so far as to keep their camera kit in a cooler box to keep it cool, if you do DO NOT use the cooler/ice packs, the moisture is really bad for the camera, a much simpler answer is to put a bit of white cloth (a clean hanky maybe?) or a bit of one of those silver space blankets over the camera when it's not in use, it'll help reflect the heat away.
A thick padded camera bag will keep a fair amount of heat off, but again don't leave it out in the sun all day.
The beach. Sand and salt water are your deadly enemy! Get them on your camera and your most lightly going to get a problem, a dunking in salt water is usually terminal for cameras, and sand gets in everywhere and grinds up the workings. A friend of mine has a compact they took to the beach, every time the lens comes out it makes a horrible grinding scraping sound from a tiny bit of sand that got in, it'll not last long I suspect.
Also it's worth noting that many mosquito repellents contain a chemical that melts plastic, indeed the one we had in the army was so strong it used to melt the rifle stocks and our plastic compass, that wouldn't be good for your camera either.
Same with suncream, nasty greassy stuff getting on the camera can't be good for it..
Probably the simplest answer is a cheap waterproof camera...... I really must buy one!