Prince Rupert's Drops are unusual glass objects made by dripping molten glass into water. The exterior is very compressed while the interior is under great tension. You can hammer on the head of a drop and it won't break but if you barely wiggle the tail, the whole thing explosively shatters. It's particularly amazing in super-slow motion.

If you loved me, you'd buy me this all-glass complete brain artery model from Farlow Scientific Glassblowing. It's $4,000. At least I didn't ask for the full-body complete artery model!