Hmmm, dunno where to start... Circumvallation is pretty awesome though, as is classical siege craft in general.
The Roman engineering at the Siege of Masada was also pretty badass.
And I always found it rather funny that the Rhodians beat back Demetrius I of Macedon and his Helepolis (clearly the dude was not well endowed by the Gods ) then melted it down to make the Colossus of Rhodes.
Ah yes, Helepolis, "The taker of cities" I don't want to even imagine how long that monstrous bastard took to construct, let alone getting it into position.
And come now, we know that all "Civilised" folk have smaller genitalia. Well, according to the Roman's at least
Love how having a massive schlong was a sign of being a member of a Barbarian culture. xD
And as an idea for a vague focal point for discussion. Was considering if anyone would be interested in going through the political and social evolution of Rome, from Monarchy - Tarquinius Sextus, to the birth and evolution of the Republic, all the way up to the dissolution of the traditional power of the Senate and the introduction of the Caesar's.
And yes, that is indeed what I term as vague...