Tough? Damn right they are, when I was much younger and my A500 was relatively new to me, I was taking it downstairs to use on the big TV when it slipped form my hands at the top.
It tumbled end over end smashing repeatedly on the steps until it reached the ground floor, hurtled down the corridor and smashed the plate doorway glass window (which didn't exactly please my parents) at the front.
I was horrified and very gingerly picked it up, and checked it over. There was no visible damage so once it was back in my room (after the telling off, why do parents never accept that accidents do happen y'know... accidentally?) I plugged it all in. It worked first time.
I booted it up the other day too, that was probably 1990-ish when it took a tumble :-D
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AS for weird stuff I've only found dead insects, chewing gum (in a disk drive) and some newspaper clippings (A500+) they weren't even interesting ones so I just threw them away.
Andy