To assist with an ongoing project, I recently re-read Nabokov's Laughter in the Dark and I'm almost done re-reading Look at the Harlequins! and I don't recall the novels being as funny the first time that I read them. There were a lot moments in the books that made me smile, which I marked in the margins with a lonely LOL, but there are other moments where the acronym gets an accompanying exclamation point that indicates that I literally laughed out loud - on the subway.
Here's an example of a LOL where Albinus and Margot are frolicking at the beach:
He splashed in after her. She turned toward him, laughing, spitting, wiping the wet hair from her eyes. He attempted to duck her, then caught her by the ankle and she kicked and screamed. An Englishwoman who was lolling in a deck-chair beneath a mauve sunshade reading Punch turned to her husband, a red-faced, white-hatted man squatting on the sand, and said:
“Look at that German romping about with his daughter. Now, don’t be so lazy, William. Take the children out for a good swim.” p114
But here are two examples of LOL! moments:
In this scene, Albinus suspects that Paul knows about the affair.
She was cuddled in a corner of the sofa, relating slowly and minutely the plot of a play which she had seen. Her pale eyes with the faint freckles under them were as candid as her mother’s had been, and her unpowdered nose shone pathetically. Paul nodded his head and smiled. She might have been speaking Russian for all he knew. Then suddenly, and for one second only, he caught sight of Albinus’ eyes looking at him over the book he was holding. p 73
Here's a bit of advice that Rex shared with the couple:
“One can’t build up one’s life on the quick-sands of misfortune,” Rex had said to him. “That is a sin against life. I once had a friend who was a sculptor and whose unerring appreciation of form was almost uncanny. Then, all of a sudden, out of pity he married an ugly, elderly hunchback. I don’t know exactly what happened, but one day, soon after their marriage, they packed two little suitcases, one for each, and went on foot to the nearest lunatic asylum. In my opinion, an artist must let himself be guided solely by his sense of beauty: that will never deceive him.” p 181
And this was a LOL! moment for me in Look at the Harlequins!:
I might have been displeased by the tolerance she showed Basilevski (knowing none of his works and only vaguely aware of his preposterous reputation) had it not occurred to me that the theme of her sympathy was repeating, as it were, the friendly phase of my own initial relations with that faux bonhomme. From behind a more or less Doric column I overheard him asking my naive gentle Annette had she any idea why I hated so fiercely Gorki (for whom he cultivated total veneration). Was it because I resented the world fame of a proletarian? Had I really read any of that wonderful writer's books? Annette had looked puzzled but all at once a charming childish smile illumined her whole face and she recalled The Mother, a corny Soviet film that I had criticized, she said, "because the tears rolling down the faces were too big and too slow."
"Aha! That explains a lot," proclaimed Basilevski with gloomy satisfaction. p 117
By the way, there's a copy of the 1969 film adaption of Laughter in the Dark on Archives.org.