The Batman and Robin scene in part 1 of the 1996 Christmas trilogy, "Heroes and Villains". Brief summary: Del Boy and Rodney are going to a fancy dress party as Batman and Robin, but their three-wheeled van breaks down en route. As they're in a rough part of London they decide to run to their destination through the back alleys so as not to draw attention to themselves. Cut to a female councillor being mugged in a car park, until the Batman theme plays on the soundtrack and Batman and Robin come charging out of the fog. The muggers scatter.
They then proceed to enter the house, going "Na-na-na-na" and spraying silly string, only to discover that the party is now actually a wake, with all attending in funeral wear. They quickly try to apologise to the man's son, only for him to reassure them that it's fine;
Son: Don't be [sorry]. I'm sure the old man is up there right now, having a bloody good laugh at us all!
Boycie's smug line before the above;
Del Boy: Boycie's come as the Penguin!
Boycie: No Del Boy, not the Penguin. More like... the Joker.
In "May the Force Be With You", Del managing to use Slater's vanity and ego against him.
DI Roy Slater: There's your immunity from prosecution, in writing - you've less chance of being pulled than the Queen - for the final time of asking, who nicked the the microwave?
Del Boy:I did!
The second time Slater gets his comeuppance doesn't belong to Del, but to Slater's own partner Hoskins. As Slater's driver, he makes a "wrong turn" towards a police blockade, revealing that they knew about his involvement with the diamond smugglers and were trying to catch him in the act. The real CMOA comes when Slater tries to bribe Hoskins, who responds with an Ironic Echo from a previous conversation.
Hoskins: You seem to forget, sir; I don't think I only do my job. (reveals a wire in his coat)
The third time pushes the Trotter brothers to borderline Magnificent Bastard territory. They blackmail Slater, with the promise that they will send to the police, a photocopy of a letter from a diamond merchant regarding 10 undiscovered diamonds that Slater had kept aside before the smuggling racket fell through. They tell him to divorce Raquel, leave Peckham for good and keep his mouth shut about his marriage to Raquel.note This would have tarnished Del's image and no one would do business with him. Slater complies and leaves, but true to form when it comes to the Trotters there was an element of bluff; the photocopier was never working. Good old Del Boy, he may a chronic liar, but that's why we love him.
In "A Losing Streak", a crowning moment for Del when after playing Magnificent Bastard Boycie at high stakes poker, he bets everything he owns on the last card stating his belief that Boycie is bluffing; Boycie managing to cheat and replace the cards dealt to him with four kings. After Boycie reveals his hand, an apparently shocked Del keeps Boycie hanging on by stating he just has "two pairs" before revealing that this is "one pair of aces... and pair of aces." The conversation that follows this.
Boycie: Where did you get those bloody aces?
Del Boy: Same place you got those kings. I knew you was cheating.
Boycie: Oh yeah, how?
Del Boy: Because that wasn't the hand that I dealt you!
In the hospital after Cassandra's miscarriage a loud, obnoxious, and irate patient is loudly abusing the hospital staff and other patients as he is demanding to be seen first. His condition? He took a bunch of pills but can't remember what they were because he was drunk. As he continues his loud-mouthed tirade, a heartbroken Del steps out still in full hospital scrubs, sets his jaw, then steps up to the idiot and lays him out flat with a single punch.
After Del is conned out of his grandmother's priceless painting by his new upper-class, antique dealing girlfriend, she taunts him by asking if he really thought she would be attracted to someone like him. She then tells him she's had the painting legally registered to her, with her parents signing sworn affidavits that it's been in their family for generations. Cue Del admitting his relief that he's finally rid of the painting, having known for years how much it was worth, due to his gran being a cleaner for an art-dealer.
Miranda: And this Mrs Mop, she examined it, did she?
Del: No, she didn't examine it... she nicked it! Good luck, sweetheart!
There's an understated one in the very last episode, "Sleepless in Peckham" when, in the middle of making a very valid argument about Del wasting money they haven't got, Raquel makes the somewhat daft and irrelevant comment "only women bleed". Del points out that he's suffered plenty, what with losing his parents and having to look after both Rodney and Granddad at a very young age. Raquel is silenced and leaves theroom.