Every year the power of the news is twisted to an evil purpose for one day, turning trusted reporting into an elaborate prank.
April Fools' Day is like a sacred right of passage for some outlets. You don't really exist until you convince a half dozen people that the Dreamcast 2 is real, or that EA is acquiring Valve. While the internet is often thoroughly saturated with falsehoods on April 1 to the point of predictability, a gullible few continue to fall victim.
In past years, the infamous pranksters at Electronic Gaming Monthly have had their readers convinced that a Lord of the Rings kart racer was in development, and that Apple was entering the handheld gaming market with a device called the iGame.
Today the joke turned real, for an instant, as Xbox 360 Fanboy reported on the existence of a LEGO Halo video game, all based on a magazine scan from EGM. Unfortunately for the fanboys, they forgot to check the date on said magazine.
One amusing byproduct of the April Fools' phenomenon is that the 24-hour paranoia can end up obscuring factual stories. Google's Gmail service was announced on the day in 2004, and the first news of Harmonix's Rock Band came last year on April 1. In both cases, many shrugged off the announcements, convinced of their unlikelihood considering the calendar date.
The opposite has happened too, with jokes being proven true--albeit in unexpected fashion. EGM's 2002 prank included details on how to unlock Sonic and Tails in Super Smash Bros. Melee. And now, as any fan knows, Sonic is making a real appearance in Super Smash Bros. Brawl.
Let's just hope that that Lord of the Rings racer never gains traction.