Microsoft's April Fools' pranks
So Microsoft has gone a couple of April Fools' for 2014. First, there's Clippy over at Office Online. Simply create a new document at office.com and he'll appear, although he's not interactive etc.
The second is genius. The OneDrive team has created 2001 drive, an old version of how OneDrive might have looked back in 2001. Check out the source code for more fun.