On a whim I bought pineapples from Ralphs, 2/$3. Following some instructions on the Infallible Internet, I twisted off the crown, peeled off leaves until I saw root primordia, and then gave the bottom of the crown a slice.
Various online articles were divided on the necessity of drying the crown first, and I'm impatient, so I put it directly in a jar of water:
At the bottom you can see the little root primordia:
And after all that, I still got to eat the pineapple! It was really good; I haven't had fresh pineapple in years, and I'd forgotten how good it can taste. And when I'm finished with that one, I still have the second one to eat.
I do have some rooting compound lying around; if I were to daub some on my second crown with a Q-tip, would the water just wash it away? Or should I daub it on and it sit for a few days before putting in water? Or is this a perfect opportunity for a semi-controlled experiment?
Side-note: I'm flabbergasted that I can buy a big fruit like this for $1.50/each when it takes them _2_years_ to grow, and you get one fruit per ginormous plant. I can't believe anyone makes any money growing these.