It's the day to go crazy playing pranks and who better to lead the fool's brigade than Google. Starting with finally realising the dream of a olfactory search engine - Google Nose, the internet giant has pulled off perhaps the most convincing prank of the year.
If you can get people all over the world to start asking why they can't detect the wet dog smell when Google Nose tells them they should be, you really have pulled off a good one.
The serious-sounding senior executives extolling the virtues of the 'new Google experience', helps of course.
Google - in its inimitable style - doesn't stop there. Google's new Treasure Maps (or Mode) encourages you to search for hidden treasure left behind by William "Captain" Kidd (that's a clue) with a dead serious marine archaeologist telling you all about the legend.
And the legend goes, Kidd screamed out just before he was hanged, "Two hundred bars of gold and Rick's dollars manifold, concealed in the realms of the unknown." Hats off to the poker-faced marketing manager and product specialists who complete the suspension of disbelief. To the readily gullible (and those who forget what date it is), it's all extremely convincing.
Gmail, not to left behind, introduces Gmail Blue, apparently six years in the making. "It's Gmail. Only bluer," says Richard Pargo, project manager.
"We tried orange, brown. Brown was a disaster." Believe it. Gmail Blue is inspired by nature "but better than what nature created". Again, kudos to the deadpan expressions and dead seriousness with which Google execs deliver their 'performances'.
YouTube's attempt at "finally picking the winner" and "shutting down" however was less than convicing. Guys, take a few tips from your parent company and get with the programme, would ya?
Twitter too joined in and introduced Twttr, the vowel-less microblogging site (you pay if you want to use vowels).
The inspiration, says Twttr, came 'The Wheel of Fortune' game show, where contestants regular shout out, "I want to buy a vowel." Best of luck with the new revenue stream, Twttr.
Facebook came through with its prank - Facebook Friend Fence, with unlimited access to yours and 20 other friends' profiles. You pay for the rest. Naah. Not convincing and posting it through a fake Mark Zuckerberg profile page didn't help much either. Better luck next time.
Various news websites also did their bit - "Scientists breed rabbits with human ears" by The Telegraph, "Pope shuns traditional Popemobile for more austere alternative" (shows a donkey-drawn cart 'if it's good enough to carry Jesus into Jerusalem, it's OK for me,' says Francis, speaking from a stable in Rome) by The Guardian and "Nasa's Curiosity rover quits Twitter after abuse from trolls" by the BBC.