I've done all the generic stuff, and most of the things listed in this thread. Here are two I don't think you've heard before:
When I first got into Animorphs at about age five, I wore a spandex leotard under my clothing for seven years straight. Just in case. I also wore a tight covering over my ears when I slept, so I couldn't be infested in my sleep. My parents thought I was nuts, but didn't stop me.
I drew Andalites, specifically Ax, on my notes. On day in math, I didn't realize that my teacher was going to collect the sheet we were working on. I was in the bathroom when he took it off my desk, and when I couldn't find it I figured I had already shoved it into my mess of a binder. The next day he handed them back. I just stared in horror when I realized that he had taken mine. I have this mad crush on Ax. I'm not going to lie. Not only was he doodled all over the blank spaces of my paper in hearts, I had written "Isthill" in place of my last name! My teacher looked at me weird for a month.
...THIS WAS LAST MONTH.