Poor Elmo came down with a respiratory infection and has been on an antibiotic for about ten days, and still has at least two days of it left. He finally perked up now and is doing great (investigating one of our terrariums, below). The vet said we caught the infection really early, but after a couple days of treatment he was in tough shape and didn't even want to eat on his own.
This is the first time he's ever been sick during the four years we've had him (he had two previous homes before we adopted him). I'm hoping he doesn't ever have to suffer through an infection like this again!