Tongue

Put a dry pill on your tongue.

Stick your tongue out. Look into a mirror.

Here's the kicker: Try to make the pill stop moving. I bet you my bear-flavored Pringles that you can't make it stand completely still. I don't know what the deal is with your tongue. It may as well have chronic Restless Leg Syndrome.

Horrible personification and subliminal pill-popping advocating aside, I decided to test my own challenge. I grabbed a <Insert Medication Brand Plug Here> and stuck it on my tongue in the hopes of making it come to rest. After twenty minutes of teary-eyed concentration and inward criticism of my complexion and gabbled comments on my eyelash length and my newfound discovery of the porcelain cow in the open cabinet above the toilet (I'm serious), I gave up--I couldn't do it. I failed.
Why not you? Try it out, see if you can do it. I know of at least one person who can. His name is....Michael Jackson.