Best April Fool's Day joke that you pulled while in the Military?

Had a Lt a couple years ago in Afghanistan that loved to play practical jokes on me. I heard him bragging that he did not get charged for the 30 days of pre-deployment leave because his XO buddy hooked him up. Pissed me off because he was saying this to his enlisted Marines. I printed out some bogus email traffic that I made up from the BN CO about how there was an investigation opened regarding officers fraudulently not being charged leave. The Lt was terrified that he was going to be court martialed, kicked out and ruin his chances of getting into business school later down the road. I heard him on the sat phone talking to a lawyer buddy about it. I let it go about a week then walked into the office, cleared the room of everybody except me and him and said, "Sir, I need to read you your rights." He started tearing up and looked terrified. I told him that it was all a practical joke, I hope he learned his lesson and he better not ever play another practical joke on me cause I will pull out all the stops. It took about 10 mins for the shock to wear off and he never said a word to me again after that. And yes, he wound up getting charged for pre and post deployment leave. I made sure of that.

I heard someone say once that he and a buddy slipped rubber hamburgers into the chow line

Trouble was no one noticed

have fun getting court martialed for that...