I am particularly captivated by the Roman system of government as it was during the late Republic -- magistrates, comitiae, the cursus honorum and so on. Of course, anyone who dabbles in this area of specialisation soon finds it impossible to ignore the events that led to the rise of the Augustan Principate, so the Civil War and events related to it also fall within my range of interests.

As for the great man himself, there's no contest: I am definitely casting my lot with him. I've long admired Caesar's military genius (Gaul in particular, but I'm also beginning to read up on his campaigns in Britannia), and his political skills are beyond reproach. (Well, perhaps not completely beyond reproach, but he definitely did an admirable job as a statesman.)