It turns out that the Blind Snake is the smallest snake in the world. They're smaller than worms I've used for fishing.
I've since found quite a lot of them in my yard, usually while fixing a broken sprinkler. They seem to stay underground. I've heard that they eat ant eggs, and given our Fire Ant problems down here in South Florida, I'm happy to have these Blind Snakes around even though they are not native to Florida.