Carl seems to have ear mites, so I'm taking him to the vet. I got him the carrier this morning and just put him in it to see if he'd fight. He did not fight. I'm afraid we're going to have some trust issues after I close him in and take him on the bus though.
UPDATE: It's an allergic infection according to the doctor, so Carl got a steroid shot and an antibiotic shot, antibiotics for me to administer at home and Advantage just in case it was fleas.
Carl cried all the way to and from the vet on the bus (he may have been swearing at me in Cat; his meows had a particularly strident tone), but was so calm for the vet and the assistant and the shots and everything. He's now lolling in a patch of sunlight on the carpet, purring. He's really the sweetest cat ever.