This was an April fools prank that my friend and I did this year. It was my friend's idea, and I helped her build it! :) It is a pretty simple, straightforward prank, so anyone should try this in their house, work, or school in April Fools! (or anytime of the year :P)

The MAX4466 detects the sound level in the bathroom, and when there is an external sound like closing the door, the Arduino will start playing a laughing sound using the VS1053 breakout. We locked the door where the Arduino was sitting and placed a pair of rain boots to trick as if there was a lady sitting on the toilet, laughing hysterically. As you can see from the video, it was quite creepy, and we were successful in scaring people. The best part was when people would come out from the bathroom and tell others to go in, just to make sure that they weren't the only ones getting scared from this. It was quite hard not to laugh when seeing people's reactions to this.

Step 1: Assembly

Supply List:

- Arduino
- a pair of rain boots
- an external speaker (any kind is ok!)
- VS1053 Codec + MicroSD Breakout (http://www.adafruit.com/products/1381)
- a headphone jack that will connect your breakout to the external speaker
- (shown in the picture: to the right of the VS1053 Breakout)
- MAX4466 (the microphone amplifier) (http://www.adafruit.com/product/1063)
- battery with a battery holder to power the Arduino

1. To the Arduino, hook up the VS1053 Breakout and the headphone jack as told in their tutorial
https://learn.adafruit.com/adafruit-vs1053-mp3-aac...
2. Connect the MAX4466 on the Proto Shield on the Arduino.
-facing the microphone towards you; far left is to analog pin, middle is to ground, and the far right is to power.
3. Upload the code. (found in step 3)
4. Connect the external speaker to the headphone jack.
5. Connect the battery to the Arduino for power source.

Now, you are good to go!

Step 2: Code

The code for this project is posted on my blog:

ardututes.weebly.com/bootsprank.html

* When uploading this file, add the "laughing.mp3" file in the same folder as your code so that the Arduino will know which file to play.This "laughing.mp3" file can be anything from a laughing man to a laughing child. (Laughing is a little better than crying.. Crying could actually freak some people out :P)

Step 3: Enjoy Your Prank!

This is what your prank would look like!

Just set all your things up on the toilet and place the boots on the ground to trick people into believing that there is a person inside the bathroom stall. Then, lock the door from the inside (and crawl outside after doing that), and you can leave and listen to people telling stories about the "laughing lady in the bathroom"!!

Happy April Fools! :D