I don't usually play pranks for April Fool's, because it's disadvantageous when everyone else's guard is up. But this year, despite my peaceful non-involvement, I was pulled in by Google Blogoscoped.
I came into work on Monday to find an unexpected email thread from Googlers, asking if it was true that I posted to Google Blog announcing GDrive.
Here's the forum where this prank originated.
Google Blogoscoped created a fake blog "googleb1og" (the number 1 instead of the letter l) and wrote a prank post. After it was crawled by blogsearch, they replaced the blog to redirect to a non-existent entry in the real Google Blog, to make it look like Google retracted the entry.