Defacing your own pictures to look like the Joker from the Batman movie The Dark Knight.
Here are the steps to jokerization:
1. Find a good picture of yourself
2. Copy and paste it into Paint
3. Using the pencil or paintbrush tool, blacken your eyes
4. Using the aforementioned tools, switch to the color red and draw a big smile across your lips
5. Writing "WHY SO SERIOUS" on the picture is optional
In response to The Dark Knight, many people have jokerized their pictures and put them up on Facebook.