Chaotic good combines a good heart with a free spirit.
A chaotic good character acts as his conscience directs him with little regard for what others expect of him. He is kind and benevolent, a strong individualist hostile to the claims of rules, regulations, and social order. He hates it when people try to intimidate others and tell them what to do. He will actively work to bring down unjust rulers and organizations and to liberate the oppressed. He finds lawful societies distasteful and will avoid them, often living as a nomad or hermit.
Noble rebel leaders fighting corrupt or venal regimes, vigilantes acting for what they see as the greater good, mercenaries who only work for the "good guys" and anyone who "robs from the rich to give to the poor" are all examples of chaotic good characters.
Characters
Some of the characters identified as Chaotic Good in the Forgotten Realms setting include:
Dove Falconhand
Drizzt Do'Urden
Elminster Aumar
Imoen (Neutral Good in the games)
Laeral Silverhand
Qilué Veladorn
Volothamp Geddarm
Non-canonical:
Coran
(Minsc is a canonical character whose non-canonical version is known to be Chaotic Good.)