why did my pyrex glass contrainer randomly shadder?!

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wow, you really should call them and complain. that is strange-- if it was just on the counter at normal temperature then with scrambled eggs... it just doesn't add up. pyrex is supposed to be tempered glass and shouldn't shatter-- it's not like the temperatures were two extremes or anything.

put up a fuss with them and they will surely compensate you.

1-800-999-3436 Pyrex Customer Service

Glass will sometimes shatter if exposed quickly to two different temps such as taking a pyrex dish from the hot oven and placing it immediately onto a marble slab used for cooling.

The eggs don't sound hot enough to be a problem, and since the glass dish was room temp first that shouldn't be a problem either. However, any glass can shatter if it's first had an impact that creates unseen microcracks.

For the past few years too, a lot of "Pyrex" containers have "exploded" (sometimes after just sitting on a counter awhile) and been in the new especially because they've been made from a poorer kind of glass than they used to be (since the company was sold, in the mid 1990's). Usually that happens after a hot dish is put onto a cool or wet surface though, but can definitely happen without touching it:
http://www.google.com/search?q=exploding…
(The new manufacturers have said though that it the new glass isn't less strong, etc, --which no one else agrees with--or that it's always been operator-error when that happens, etc. Most others who are unbiased and tested this out agree that it's a real problem though, like Consumer Reports Jan. 2011, etc.)

"Pyrex in US used to be made of borosilicate glass. Now the Pyrex bakeware pieces you see are made with soda lime glass. (Pyrex *lab* glassware is still made with borosilicate glass.)
http://www.amazon.com/PYREX-Brand-4320-r…
In short, borosilicate glass has a very low thermal expansion coefficient which is why scientists have little problem using this borosilicate lab glassware for chemical reactions. Not to say they will never break, but they are resistant to thermal shock. Soda lime glass is not. Therefore you hear all these US Pyrex bakeware pieces breaking. I kept saying US Pyrex because European Pyrex pieces are still made with borosilicate glass.. . ."