The people at our camp pranked one of the leaders.
He was out when we alerted him by text that a camper had gone missing and we ad gone out into groups to search for her. Most of us hid while the "lost" camper and two others stayed near camp. When he came up, he was ran to and alerted that she had passed out. When he came up to where she was, we popped out and yelled "April Fools!"
I pranked my mom by telling her I was pregnant which is why I haven't had a period for 3 months then showed her a positive pregnancy test.
That is quite cruel... quite cruel....
I put some kind of a compound... potassium sulfide I think (I'm not sure my engineer friend gave it to me) in another friend's muffler... It made his car puke black smoke when he was driving, he got pulled over 3 times for it. Marvelous
I had a group of people I know and I decided to wander the campus all day. Every time anyone said or alluded to the name of our school (Mesa State) we subtly said "cock." It was great, especially when there were more than one of us in the area. Right out of the Penn Jillette book, I know.
Not really a prank, but hilarious either way. Some people didn't even catch onto it.