Queen: I do know why I wanted to see you, and I just pretended I didn’t, and I fooled you. And it worked brilliantly, didn’t it!
Edmund: It was terrific, Madam. I thank God I wore my corset, because I think my sides have split.
Not a line or a joke, but just the tiny wince of anguish on Tim McInnerny’s face every time Blackadder says:
Yes, Darling?
Not a joke, but my favorite line was by Blackadder to the Queen in “Chains”
Queen Elizabeth: And me, did you miss me Edmund?
Blackadder: Madam, life without you is like a broken pencil.
Queen Elizabeth: Explain…
Blackadder: Pointless.
I turned that into a card for my wife 
“How did you get so much custard out of such a tiny cat?”
In the final ep of Season 4 there is a fantastic (if disgusting) joke set up by an earlier scene:
Then later Melchett & Darling visit the trenches:
Season 2 being loaded on the iPad as I type…
The Black Russian, I think; that always frightens the clergy.
THE WOMAN’S INSATIABLE!
Melchett: Now, Field Marshal Haig’s plan is this; to commission a man to do an especially stirring painting for the cover of the next issue, so as to really inspire the men for the final push. What I want you to do, Blackadder, is to labour night and day to find a first rate artist from amongst your men.
Blackadder: Impossible sir. I know from long experience that my men have all the artistic talent of a cluster of colourblind hedgehogs… in a bag.
Melchett: Hm, well that’s a bit of a blow. We needed a man to leave the trenches immediately.
Blackadder: Leave the trenches?
Melchett: Yes.
Blackadder: Yes, I wonder if you’ve enjoyed, as I have sir, that marvellous painting in the National Portrait Gallery, “Bag Interior”, by the colourblind hedgehog workshop of Sienna.
We have a cat named Sod Off. A nod to Blackadder which means we can yell at the evil neighbors to sod off whenever it seems right and just so to act.
Melchitt; alas, shall I never see England more, her rolling fields, her swooping swallows…
Black adder; …and her playful sheep…
Great lines from everyone. Reminds me how much I need to get the other three seasons that I don’t have yet.
My favorite joke is from the first season, when Percy tries to explain to Blackadder just how blue the Spanish Infanta’s eyes are:
One of the absolute best scenes of the entire series is the Court Martial scene in Blackadder Goes Forth, with George as Blackadder’s defense counsel. I can’t type the entire thing out, but George’s closing statement (with its critical stage direction) is a work of genius:
George (reading from a prepared statement): Gentlemen, you have heard all the evidence presented here today, but in the end it is up to the conscience of your hearts to decide. And I firmly believe that, like me, you will conclude that Captain Blackadder is, in fact, totally and utterly GUILTY.
*
(He sits. Blackadder flips over his statement to the other side)*
**George: **…of nothing more than trying to do his duty under difficult circumstances!
Melchett as the prosecutor is brilliant, too. Although his grief over the loss of Speckled Jim is somewhat at odds with the indifference he showed about George’s pet rabbit being hit by a car.
His car.
Yes, by his car. But that too was an act of mercy when you would remember that that dog had been set on him.
His dog…
I’m not wholly fond of Blackadder, nor any other British production; but it is pure art in ‘Money’, Series 02, when somewhat relieved to discover her Majesty’s death sentence upon himself was merely a jolly jape, the chortling Lord Melchett intones:
“Praise the Lord, for the Gift of Laughter.”*
Can’t believe no one’s posted “…thick as a whale omelette.” I say that alla time.
“MacAdder and I are nothing alike. Why, we are dissimilar as two totally dissimilar things… In a pod.”
Wibble.