There's Legal Assassin, a song all about how he's the best murderer on the block.
This line in particular. It's the first time we see the shift from Nathan Wallace to the Repo Man, and it is terrifying and amazing to watch.
I'm the monster, I'm the villain.
What perfection! What precision!
When he refuses to repossess Mag's eyes, despite Rotti, Pavi, and Luigi's best efforts, in Night Surgeon.
Let The Monster Rise, when he decides to put the smackdown on Rotti
Particularly that part at the end of the song when he holds that last note for at least sixteen seconds.
Didn't Know I'd Love You So Much, for all the same reasons as Shilo.
Thankless Job, when he uses a recently-disembowled corpse as a sock puppet, lamenting how ungrateful people are to people in his line of work.
The Graverobber, in 21st Century Cure, when he stands up and screams at the many, many, many machine-gun-toting Gen Cops chasing him. There's also:
Using a corpse as a battering ram
Escaping from the GenCops, again, and taking Shilo with him
The entirety of Epitaph
Hell, basically any time Terrance Zdunich is on screen, something awesome is going down.
Basically, there's just not enough Graverobber in this movie.
Amber Sweet, at the end—when she sold the face that came off during Blame Not My Cheeks to Pavi
She has another one when she has her brothers back her as she becomes the new CEO of GeneCo and the most powerful person in the country, proving beyond all doubt that she is her father's daughter... at least, when she's sober.
In a meta sense, one for Paris Hilton, for managing to sing on the same stage as the likes of Anthony Stewart Head, Paul Sorvino, Ogre, and Sarah Brightman without making a complete fool of herself. Sure, she's not the strongest voice in the cast, but she's not supposed to be.