Found a bunch of these big fat green caterpillars monching away on the jalapeno plants. Google image search identified them as tobacco hornworms (manduca sexta).
Plucked 6 hornworms off the jalapeno plants (they have a pretty good grip for something so squishy) and flung them out into the road where at least 3 of them ended up getting squashed by passing traffic.
The caterpillars really did a number on the jalapeno plants. The jalapenos were looking big and bushy a couple days ago. The leaves from a big section of the top of the plants have been stripped off now and I had to prune off a bunch of half-eaten jalapenos.