If a worm at the bottom of your bottle just isn't enough, you might be interested in trying tequila con vibora, a beverage freely sold in Baja California, where nobody takes this "cruelty to animals" business very seriously. It's rattlesnake tequila to the gringo college students who drink the stuff as a rite of passage, and a homemade panacea to the locals.
You don't need a sandworm to make this water of life. Toss a live rattlesnake in a big, glass jar, and cover the surly critter with a gallon or so of cheap tequila. As he drowns, he coughs up a bunch of exotic chemicals that'll cure what ails ye. Or so they say. The snake is then removed, gutted, and put back in the jar to soak for several months before the concoction is ready to be dipped out and sold to brave customers. It seems that the reptile's venom is only toxic when injected, not when ingested.
I doubt this variety of tequila would go over well in the United States, even if it were legal by some bureaucratic oversight. It seems a uniquely Mexican phenomenon: you order a shot and see the bartender hand-dip your beverage out of a huge jar with a big ugly rattler coiled up at the bottom. It's primal, even mystical from a certain perspective, and it's rapidly becoming an anachronism as Mexican distillers concentrate their efforts toward bottling premium tequilas for export.
No, I've never tasted tequila con vibora, or even seen it for that matter. There's an article about it in the June 10, 2002 Los Angeles Times. And if you want to see a picture of an actual rattler-filled jar of it, presumably too graphic for the delicate sensibilities of the Times readers, there's a good one at http://www.bajaseve.com/Vibora.htm