Kevin Kling’s The Dog Says How is a bunch of essays that is roll on the floor funny (and sometimes poignant as well, but mostly just funny).
I’ll second Wodehouse’s Jeeves books, and Pratchett’s Diskworld books
Christopher Moore. His latest. Sacre Bleu is his best.
Anything by A. Lee Martinez. Monster is probably his best, but they’re all funny fantasy adventures.
Jasper fforde’s The Eyre Affair
Ditto on Christopher Moore, the first 6 Stephanie Plum books by Evanovitch, and Terry Pratchett.
Let me add the Amelia Peabody series by Elizabeth Peters, starting with The Crocodile on the Sandbank. She makes delicious fun of the intrepid Victorian British female explorer, spoofs the Victoria Holt type of Gothic romance, and throws in a lot of good Egyptology. Read in order for character development.
Also, The Herring Seller’s Apprentice, by LC Tyler. Hero a mild-mannered writer of mediocre mysteries and his bullying agent. British humor.
Georgette Heyer. For years, I never read them, because they are romance, and I was prejudiced against romance. But they are quite clever, the Regency slang and costumes thoroughly researched, and, most important of all right now, very funny. Think of them as Jane Austen light.
Go The Fuck To Sleep, as read by Samuel L. Jackson.
A short read to be sure, but I dare you not laugh!
Let’s Pretend This Never Happened: A Mostly True Memoir by Jenny Lawson. You will laugh yourself stupid, I promise.
Harpo Marx’s memoirs, Harpo Speaks!
Preview at Amazon’s “Look Inside” or Google Books. How he became a member of the Algonquin Round Table.
There were a lot of ups and downs until they finally made Broadway. After that, the amount of famous people he met are just astounding.
Yes.
Three Men in a Boat by Jerome K. Jerome
Seriously? With this crew, no one has mentioned The Princess Bride?
My magic number (the post number I was guessing would be the one that suggested it) was 5.
Anything by Thorne Smith.
The Cursing Mommy’s Book of Days by Ian Frazier. You will thank me when you stop laughing.
A little off what you have asked for but I have always found that when I need a cheer I just reread Jonathon Livingston Seagull by Richard Bach.
Do these adhere to the OP’s request:
?