The Museum of Hoaxes lists the top 100 April Fool's Day hoaxes of all time. A nice way to spend April Fool's Day is to peruse their gallery of unbelievable hoaxes, some of which must have taken considerable thought, effort, and even money to pull off! And when you're through with that, take a look at Wikipedia's chronology of pretty much all of Google's April Fool's jokes. Google has been pulling off these jokes ever since 2000 when they invented their MentalPlex to make searching easier :p Someday they really may invent this thing, whenever we're able to plug ourselves neurologically into the internet. For now, we'll have to settle for searching the old-fashioned way, using our current faculties.