At WorldCon, I ran into a couple of reading pronunciations I hadn't heard before.
A reading pronunciation happens when you learn a word by reading it rather than hearing it pronounced, and you guess how it's pronounced, and you guess wrong. I know reading pronunciations are common among sf readers (and presumably among people who were heavy readers in childhood in general), but I hadn't heard any lately, so these two stood out.
I don't know if I have any of my own left, but I've certainly had plenty in my time. A particularly embarrassing one for me was that I always pronounced "valise" as /'v&l Is/ (see ASCII IPA for pronunciation key); I said the word while reading a story aloud at some point in college, and everyone in the room thought I'd said "phallus." They eventually explained to me that it's actually pronounced /v@ 'lis/, rhyming with "police." (That one's also funny 'cause I know I had previously heard and liked the English version of the Jacques Brel song "Timid Frieda," which includes the line "There she goes with her valises held so tightly in her hands." But somehow even hearing that hadn't changed the pronunciation in my head.)
Anyway, at WorldCon I heard one person pronounce "novice" as /'noU vIs/ (first syllable like the word "no") instead of the standard /'nA vIs/ (first syllable like the word "nah"). I think when I first encountered that word I may've pronounced it like the phrase "no vice." Later in the weekend, I heard another person pronounce "eiderdown" as /'i dR dAUn/ (first syllable rhyming with "bee") rather than the standard /'aI dR dAUn/ (first syllable rhyming with "buy").
I don't remember who said these; if it was any of you, sorry for posting this publicly rather than taking you aside and telling you in private. I don't mean to embarrass anyone; just thought these were interesting.
Regarding "eider" and "eiderdown," perhaps it's worth mentioning a rule for German pronunciation that my parents taught me when I was a kid: in German, the "ei" spelling is pronounced like "eye," while the "ie" spelling is prounced like "ee." Or to put it another way, to pronounce "ie" or "ei" in German words, you look at the second letter rather than the first. I don't know enough German to know whether that's always true or only mostly, but it's certainly a good rule of thumb. Useful in reverse, too, for figuring out whether i comes before e or after in a German word that you know how to pronounce.