[desertrat]

Funny you should mention about the glassware and meth labs - I was reading somewhere that Anchor-Hocking changed the formulation of Pyrex for home grade measuring cups and such so that it would not withstand rapid temperature changes nearly as well as the old formula did - apparently meth making involves a lot of quenching liquids and such (i have no idea about the details. lol)

Pyrex was made by Dow Corning, but Anchor Hocking made a similar product. Corning did cheapen the formula of Pyrex kitchenware (not labware), but I think the above stated reason comes from drug addled conspiracy theories.

Corning changed the formula because common soda lime glass is cheaper to make than borosilicate glass, and the cheapened casserole dishes didn't explode in people's ovens...most of the time.