I'm gonna say it—his You Are Not Alone speech to those who have suffered from LGBT hate from the ending of his Tokyo Godfathers review. Sure, it may have worked better if he was onscreen—but his delivery seemed very heartfelt, and it even got me misty-eyed. Followed by him calling Number Six part of his family.
Meta Example: When the Hero was going to lose his laptop (and his only source of income) he started a donation pool for a new one, despite not really liking the idea of accepting charity from fans. His fans donated enough money almost immediately, and thanks to finding a cheaper laptop than he'd anticipated, he was able to pay them back almost immediately as well. The fact that he was able to do this despite not having that many fans shows how much the fans he does have care.
His defense of Xion from his Top 10 Best Kingdom Hearts Boss Battles. He goes into extensive detail about just how sad the character's situation was, defending her from all of the Mary Sue accusations. His voice actually wavers on a few occasions, and he even declares her his favorite character in the entire franchise. Cheesy though it might be, it's still very touching when you hear it.
His speech of never giving up in his Samurai Jack review, in which he tells the audience that just because someone says your work is terrible and you don't deserve another chance, that you should never stop doing what you love to do.