The aforementioned Nero really does get a bad rap for the Great Fire, though. Most historians after him for quite some time repeated the old maxim that he fiddled (or played the lyre) while Rome burned, or less anachronistically, that he sang the Sack of Illium. However, what of Tacitus, the historian that actually lived through it as a child and later wrote of it in his histories? Tacitus reports that Nero returned immediately to Rome and organized a massive relief effort and urban renovation that he funded through a combination of increased tributes from the provinces and his own funds. Then, Nero blamed the Christians for the fire, because the people demanded a culprit for the devastation, and it was either making the Christians a scapegoat or ending up being the scapegoat himself. "Fiddling while Rome burned" was the revenge of Senators upset about the significant increases in taxation/tributes that were the cost of Nero's urban renewal/bread and circus policies, that he supported the rights of the freedmen over the patrons (i.e., the Senatorial aristocracy), that he tended to pander to the lower classes in ways they considered shameful or immoral (public performances, opening theatres), and that he ruled Rome in a time of economic unrest and instability (either due to his own policies or by already-extant issues at the time of his accession); it was then subsequently perpetuated by early Christians after they finally came to power.
Ow, don't go saying Tacitus liked Nero. Because well, he frequently accuses Nero of fueling the fire, preventing fire extinguishing attempts, all to build his own awesome palace on the ruins*. He also clearly states that all these rebuilding efforts were not done out of compassion with the people, but in order to gain popularity with them. He concludes that this attempt was unsuccesfull.
((And that's ignoring the incest tales, murdering his brother, his mother, and many others, ...))
And yeah, the Early Christians didn't like Nero. For a decent reasons though, as he liked to use them as candles.
*Which is an unfortunate coincidence, isn't it.