You learn something new every day...

I am just setting myself up for my_tallest to say, in a disparaging tone, "What? You didn't know that?"...

But apparently, while the most frequently-used plural of "octopus" in American English is "octopuses", the "correct" plural form is not "octopi", but rather "octopodes", pronounced "ak-TO-po-dees". (Because "octopus" is from the Greek, you see; the -i ending would be correct if it were derived from Latin.) Of course, usage of "octopodes" is so rare as to be non-existant. Still, it seems rather wonderful, and I hope to remember to use it someday should I ever have the occasion to do so.

(This and other fun language-usage stuff can be found in the Word Court Archives, which I discovered today and got a kick out of starting to read through.)