There are three reasons why I feel comfortable admitting this disaster publicly:
a) It came from a store-bought mix (not my fault)
b) It was made entirely in an automated bread maker (not my fault)
c) The resultant bread became a bit of a science project, and science is fun.
There are many ways for bread to fail. This particular breadtastrophe was about as unleavened as a leavened bread could possibly be. When all was said and done, a pound and a half of bread had somehow baked neatly into a few cubic inches:
It was nearly 9 times the density of normal bread. I was reassured to learn that despite that, the bread was not in fact as dense as a brick. For your edification, here's how the bread stacks up against a few other materials.
Notably, the bread is more dense than crushed asphalt. Mmmmmm... Pavement. I like pavement toasted with a bit of butter, then dipped into hot cocoa.
Also of interest, the bread is essentially isodense with elemental potassium. Presumably, the bread would not burst into flames if you immersed it in water, but I didn't actually try that.