Ditto! I also unintentionally memorized the “Hold Fast” chant from Mervyn Peake’s Gormenghast. I just liked it a lot and read it until it stuck.
Other than that I know a few bits of other poems by heart, particularly pieces of Browning and Swinburne, who are my favorites.
I had to memorize all the US Presidents in order for a class in 8th grade. I still have that committed to long term rote memory and it’s occasionally useful (I’m a history buff). Problem is, I only memorized up to Jimmy Carter, who happened to be the President at the time, so while I can fly through the list up to Carter, dredging up Reagan…Bush…Clinton…GW Bush…Obama…Trump…Biden requires considerable active memory recall, which is weird when you consider they’re more recent.
When I was a kid, my Dad taught me a mnemonic rhyme in which the words started with the last name of all the Presidents in order. Unfortunately, he learned it when he was a kid, so it only went up to Hoover. I can usually remember all the Presidents post-Hoover.
I remember my high school alma mater. Why? The class officers wanted those who could sing to memorize it so we could prod the rest of the class into joining along during the graduation ceremony.
Sung to the tune of “Dedicatory Overture”
High in the hills of Habersham
Silver and Blue our colors fly,
Honored with love and loyalty
Central, your name shall never die.
Central O Monument of glory
We love you more and more each day.
Tears will flow when we leave these halls
Central, your name shall never die.
I’m sure that line was delivered with no satirical intent whatsoever. Because who doesn’t well up with tears fondly remembering high school, right?
Musical notation: treble clef, bass clef and time values.
I still remember the landline telephone number for the house in another state I haven’t lived in for 48 years.
All of the verses to the “Bottles of Beer on the Wall” song.
I remember the very first locker combination I ever had in junior high. 43-45-17. However, I don’t remember any other locker combination I ever had since.
Oh, and Pi to fourteen decimal places.
ETA: and the first four Pythagorean Triples where the first two of the triple differ by one. (3-4-5 being the first and most famous).
Quick, what’s your fifth general order, Marine?
I frequently invoke this one when it’s Miller Time.
It’s ironic that we get that from when Jesus advised us NOT to recite rote prayers but to pray sincerely and from the heart.
You could get yourself a 72-hour hold reciting that one. It makes “The Great Panjandrum” sound positively lucid by comparison. 
That’s a good one. I know it as well.
I know part of Die Lorelei.
I know a lot of theme music from '60s and '70s sit-coms.
But really, it’s impossible to enumerate everything in my head. My head is a [Huntz Hall] vast suppository of useless information. [/HH] It annoys the hell out of my wife that everything reminds me of something.
The list is correct, but we don’t call them dative adverbs, but prepositions that require dative.
Now I am going to have a look at that Panjandrum. I have tried the Jabberwookie, I think it’s hilarious too, but it beats me.
Duh, of course. Thanks for the correction!
Deliberately:
Jaberwocky and Father William (Lewis Carroll), The Yarn of the “Nancy Bell” (W.S. Gilbert), The Betrothed and Gunga Din and Tommy plus stanzas out of several others (Rudyard Kipling).
All that glisters is not gold. . . etc. from The Merchant of Venice
Preamble to the Constitution, Gettysburg Address.
All the SSNs for my wife, my kids, and I.
Any number of songs and prayers.
Inadvertantly:
My first driver’s license, my current driver’s license, and my current phone numbers and the number of my wife (plus I still remember our number from 60+ years ago). The ID numbers for the Programs, PROCs, and JOBs from a subsystem in my first job as a programmer. My license plate number from my first car. I recall the address of every place I’ve lived (Only 8 of those over 70+ years thus far.)
For several years I knew my most frequently used credit card, but some hacker forced a change in cards and I do not recall all 16 digits of any cards I have now.
Now it’s running through my head, and I’m not from Chicago, in fact I grew up in another state.
But I had college friends from the Chicago 'burbs who would torture each other with that. I really should look up the actual commercial…
I know most of it, but I can never remember the last verse.
Most strikingly, dozens and dozens of dates of various events of my life. I can even often remember the exact day of the week and what the weather was like when they happened.
Also :