Beecher's first Hannibal Lecture to Schillinger at the end of season 1, where he threatens to mess up his parole by pulling him into a brawl. His sarcasm is gold.
O'Reily's time in the hole. Quick montage of the effect it's taking on his mentality, culminating in him turning into a raging madman. Then the guard comes in.
O'Reily: (casually gets to his feet) Piece of cake.
"You have ten minutes to get your hand off my dick."
Father Mukada realising the confessor asking about the Eucharist (eating the body of Christ) is a notorious inmate who killed and ate his parents.
Vern Schillinger trying to swallow his racial pride to approach Adebisi about having Beecher whacked. After the two stare at each other in silent contempt, Schillinger realises even he can't sink that low.
Martin Querns. Every time he speaks.
Omar White, in a similar fashion. Mostly, he's either annoying, funny or both.
Shirley Bellinger calmly telling Warden Glynn that the guard leading her off to be executed has been "coming into my cell every night and fucking me."
When Moses calls out Lopresti on not getting fired over it.
Moses: You was eatin' that pussy like chicken chow mein.
Adebisi getting rejected by Shirley Bellinger because he's black. His reaction is priceless plus Pancamo teases him about it once.
Adebisi: "Suck my dick now..."
When the guards yank him away, you can still hear him in the background yelling "SUCK MY DICK!!!"
The black death row inmate who punches through the cell wall on which his racist neighbor is painting a self-portrait and throttles him to death single-handed.
Omar White insisting on an apology from Tim McManus after he put the latter in hospital. Again.
Keane's wedding, where Adebisi had to stand in for his bride.
Adebisi on drugs, seeing the Narrator talking to him from his computer screen.
This scene during Adebisi's drug withdrawal is also awesome.
What about later on in that withdrawal. Alvah Case comes to interview him about the riot and he's standing there fondling himself. They open the window and he looks up and simply says 'You want...to lick...my balls?' with a hopeful look. They turn around and shut the door without a word.
The scene with Hill accusing Beecher of farting while they share the same pod.
A blink-and-you'll-miss-it moment in the same episode; during one of the Em City meetings, Adebisi walks in and puts one of his trademark hats on O'Reilly's head.
Investigator Burrano asks Rebadow why he didn't tell Nino Schibetta not to seek revenge for Ortolani's murder when God told him to.
Rebadow: Just 'cause I talk to God doesn't mean I'm crazy.
Schillinger flipping out when his name is mispronounced for the umpteenth time.
Schillinger: Schillinger! God damn it, Schillinger! I've been here nine fucking years, you'd think you'd figure out how to say my goddamn name!
This little exchange between the inmates in solitary:
Clayton Hughes: "Robson you are one ugly motherfucker."
James Robson: "I don't see you modeling in Milan... you black bitch."
Miguel Alvarez: (Shot from behind with his pants down) "Hey shut the fuck up, I'm tryin' to masturbate!"
Hughes: "Hey fuck you Alvarez!"
Random CO: "Shut up! Warden on deck!" (Warden Glynn walks in)
Alvarez: "Hey Warden you get me excited! Why don't you hold my dick?"
Rebadow tying his little kerchief around his head Rambo-style, doing sit-ups while quoting Sun Tzu's The Art of War, and then miserably failing to kill Busmalis in what basically amounts to two confused old men fumbling around in the dark.
Schillinger awkwardly cradling the baby doll in the nursery, quickly putting it in the basket when the CO walks in, realizing he's put the white baby doll in the same basket as a black one, and then segregating all of the dolls.
Loewen: You know Vernie, I gotta tell ya, I never thought you were the brightest bulb in the chandelier. You always had this HUGE ego with nothin' to back it up. Always coming up with these big plans with no balls behind them. Shit, if it wasn't for your daddy, I wouldn't have given you the time of fucking day! You're a disgrace to the brotherhood.
Schillinger: ... I have balls.
Loewen: Speak up, boy, I can't hear ya.
Schillinger: ... Nothing, sir. (Leaves, dejected)
Busmalis playing basketball.
Though a rather disturbing moment in and of itself, Cutler forcing the spoon up Robson's anus and Robson's pained grunts. The pained grunts being immediately topped off by the distinctive "HUH!" voice at the beginning of the credits.
Clayton Hughes' pathetic attempted takeover of ad-seg, including other inmates heckling him and fellow inmate Greg Penders actually trying to help him before realizing people are entering the hall and promptly scurrying back into his cell.
One inmate upon seeing Schillinger dead on the ground: "That mothafucka's DEAD!"
Unit Manager Tim McManus forms a brief liaison with prison guard Claire Howell. When he tries to break off the relationship she assaults him in his office (to the delight of watching inmates). Their response to the assault is hilarious.
Claire: "What the fuck you doin with a cigarette Pancamo?"
Pancamo: "Smokin' it."
Claire: "Put it out! Now. Or I'm coming in there!"
Beecher and Schillinger's duet in the Musical Episode. Neither actor is much of a singer, so they turn it into a comedy/vaudeville routine.
Robson and Keller both going to kill Zabitz. He backs into a corner, faced with certain death...and keels over of a heart attack. The look the two would be killers give each other before bolting is priceless.
Especially given the blustering threats they'd been giving each other a moment before, then...
When Robson reports back to Shillinger, and he just laughs.
Shillinger: I told'em to lay off that red meat.
Sister Peter-Marie's reaction when she's informed that the prisoners voted her as the sexiest woman in Oz.
Alvarez agrees to be the stage manager for Macbeth so he can boss everyone around; the next few episodes have him shouting at people and making some truly fantastic faces◊ in response to the inmates' acting.