Look out Superman,
Kryptonite is real. To bad it's not green, but it might be useful on certain applications. Wouldn't it be fun to say, "My iPod is powered by kryptonite. Let's send one to Superman as a gift!".
It hasn't been long since Captain America died, and now we have someone doing this:
Captain America Arrested With Burrito In Pants. The story is worth a good laugh.