I'm reposting my list with explanations
Greek
Lycurgus - For establishing the Spartan constitution, a fascinating document.
Draco - For his 'execute everybody who does anything' law code.
Peisistratus - For laying the groundwork for Athens' golden age
Themistocles - For his sneakiness at Salamis
Sophocles - My favourite of the 3 great Athenian tragedians
Pericles - For the Parthenon
Alcibiades - For being the original playboy
Socrates - For being the original troll
Aristophanes - For making the first fart and penis jokes in history
Herodotus - For inventing history
Epicurus - For spinning a good ethical theory out of atomism, the Greek metaphysical theory that got closest to the truth
Phillip II - For revolutionising the phalanx and building the army that would conquer the world
Alexander - For doing the 'conquering the world' business
Agathocles - For being the most deliciously nasty ruler in Greek history. Check out the biography:
http://www.historum.com/ancient-hist...thread-32.html Roman
Appius Claudius Crassus - The head Decemvir, a really interesting period in Roman history
Cincinnatus - For giving up a dictatorship. Twice!
Marcus Porcius Cato - If Agathocles was deliciously nasty, Cato the Elder is the kind of nasty that makes you feel the need to take a stick of soap to your mouth.
Lucius Cornelius Scipio Asiaticus & Lucius Aemilius Paullus Macedonicus - Not hugely interesting characters, to be fair, but they played vital roles in my favourite era of Roman history
The Gracchi - For pursuing moral policies in an immoral world
Lucius Cornelius Sulla - For being a sociopathic political genius
Titus Lucretius Carus - For elucidating Epicurus' philosophy in poetry
Gaius Julius Caesar - Seriously?
Marcus Licinius Crassus - The richest man in human history (possibly). Look up his fire-fighting service.
Augustus - Inventing a system of government that did pretty well for over 200 years
Marcus Vipsanius Agrippa - For being the most kick-ass best friend in history
Gaius/Caligula - For all the crazy stuff he did: Incitatus, the bridge over the bay of Baiae, etc
Claudius - The last known person to be able to read Etruscan, a historian with cerebral palsy (maybe) thrust into the purple, or so the story goes
Tacitus - For being the greatest ancient historian
Hadrian - For being the first openly gay leader in world history! An example to us all

Marcus Aurelius - For keeping his head in a world gone mad
Didius Julianus - Poor, poor, Didius Julianus...
Gallienus - For keeping his head in a world gone stark raving bonkers
Aurelian - For restoring the world
Constantine I - For turning a minor apocalyptic sect into the world's leading religion
Majorian - For being the last chance the Western Empire had