Well, some would argue that being good is an advantage itself. (Socrates, for instance, maintained that a virtuous man is, by definition, happy, regardless of his present circumstances).
On a less philosophical slant...
-you can use spells like holy word and holy smite without being a part of the collateral damage. Of course, this works best if the whole party is good, but even if there is just a good cleric and you, it can work to your advantage.
-in some settings, you are less vulnerable to certain spells--in Arcanis, for instance, glimpse of the cauldron is less effective against good characters than against evil ones.
-Expanded class options. You can be a sacred exorcist (one of the better cleric prestige classes). You can multiclass with paladin (pretty nice if you're a melee sorcerer--IMO, Paladin 2/Sorcerer/Spellsword/Eldritch Knight/Abjurant Champion is a lot better than Fighter/sorcerer/the rest). You can be a Radiant Servant of Pelor. IIRC, Combat Medic also requires good alignment. Maybe not at the same time, but you also have to be good to be a holy liberator.
-(If a cleric) you can craft a holy weapon without jumping through non-core hoops to get the glory domain.
Also, note that the disadvantages of being good mostly show up at the low-mid levels. At higher levels, shield of faith is better than protection from good anyway, blasphemy works just as well against neutrals as against good characters, and unholy aura is nearly as effective against neutral characters as it is against good characters.