Disappearing Cheshire Cat shot glass!

I've been working at this idea for awhile: when etched glass is in contact with liquid, it becomes nearly transparent again. I thought about what designs would work well with this idea, and I hit upon the Cheshire Cat. I etched the cat inside the glass, but etched the grin on the outside, so when you pour water into it, everything disappears, leaving just the grin.
I plan on making a much cleaner/neater/preciser glass sometime, but for now, the concept comes through fine. (There's a video of the glass in action, if you scroll to the bottom of this post. And for low-bandwidth folks, there's a hilariously crappy animated gif instead.)

Before liquid

Pour booze in, and voila!
(It's water, actually)

Video of water being poured in!

I warned you it was hilariously crappy