archimedes of syracuse (287-212 BC) was perhaps the greatest mathematical mind of his day. a student of the mouseion of alexandria, archimedes returned to his home city of syracuse to become an inventor of great renown.
he is reputed to be the originator of the theory of fluid displacement (and, related, an early critic of your primitive notions of modesty), a quick and consistent calculation method for the volume of a sphere, the archimedes screw (not a sex act, a means of pumping water), and possibly even a death ray he used on roman invaders.
in 212 BC archimedes was supposedly killed by a roman legionary who had been instructed to find the great mathematician and bring him before his commander, marcellus. while this legionary looked for his quarry, he stumbled upon a scruffy old man drawing circles in the sand; the old man snapped at the legionary not to scuff his circles, and was killed for his impertinence. naturally the old man turned out to have been archimedes. heh. cosmic irony.