"Google loves a good April Fool's Day joke. Sometimes the joke is even that it isn't a joke. Take a tour of some of Google's best April Fool's Day jokes." Proving that they're not just smart, but funny too, folks at the GooglePlex churn out good pranks year after year. My favorite was last year's Gmail Paper Project. "You click. We Stack. You get."
FamilyFun's April Fools' mini-site is a fun collection of silly food (meatloaf cupcakes topped with pastel-colored mashed potatoes) and pranks. The pranks all fall into the "friendly fun" category, with none of them overly outlandish. While you are clicking, be sure to visit Printable Pranks (such as a Fake Chore Chart for parents to print for kids, and a Fake Tax Letter for kids to print for parents) and How-To Videos for recipe demonstrations.
Infoplease tells fascinating true tales about dozens of famous hoaxes from sports, science, art, and yup, even the Internet. Peruse the articles, then test your Hoax IQ with their ten-question Famous Hoaxes Quiz. "In an 1878 April Fool's Day hoax, the New York Graphic newspaper claimed that Thomas Edison had invented a machine that could do what?"
The Museum of Hoaxes has compiled two lists for April Fools' Day. The first is the Top 100 April Fools' Day Hoaxes of all time "as judged by notoriety, absurdity, and number of people duped." At the top of this list is the Swiss spaghetti harvest of 1957, as reported by BBC. "The Swiss Spaghetti Harvest hoax generated an enormous response. Hundreds of people phoned the BBC wanting to know how they could grow their own spaghetti tree." The second list is the Top 10 Worst April Fools' Day Hoaxes Ever, for attempts at humor that not only didn't work, but were downright awful.
Snopes.com, famous for de-bunking urban legends, tackles the origins of April Fools' Day. A common story is that April Fools' Day has its roots in the 1500's when the Gregorian calendar took over from the Julian. People confused by the switch, who celebrated New Year's on the wrong date (previously April 1) were teased as "April Fools." Whether that story is true or not remains "undetermined" according to Snopes. This page also discusses other April Fools' theories and folklore. "Superstition has it that the pranking period expires at noon on the 1st of April and any jokes attempted after that time will call bad luck down on the head of the perpetrator."