My personal all-time favorite - https://www.newschoolers.com/news/read/Moving-Newschoolers
The funny part about this one is as obvious as it was at the time - TONNES of people believed it. Hell, as recently as 6 months ago I've met people that say "Dude, you still work at NS? I thought you got a job in Florida or something like that a few years ago?"
Hell, the Senior VP of our division at the company was at a corporate retreat a few years back, and the CEO of the company apparently stood up in front of everyone, singled out Norb (SVP of Action/Outdoor) and said "Hey Norb - What is this I hear about sending one of your boys down to Florida without telling me?"
Maybe not the funniest prank, but damn did it go far and wide.