Have you not seen one that's like, off? The way it solidifies at the bottom?

http://s3.amazonaws.com/photography.prod.demandstudios.com/d131a872-1432-42c2-a8e5-2336405b7ba4.jpg

Funfact: if you take the glass bit off and just have the bottom on, you an melt dvds with it. Unrelated fact I was a stupid kid and used to own a copy of high school musical 2.