This collector's gallery of 19th- and 20th-century tricks and posters from the magic shop El Rei de la Màgia will enchant any budding magicians. To see some live sleight of hand, book for the shows; places are limited. They're not in English, but they are very visual, so it doesn't matter too much.
You've done the Picasso, the Miró and the MACBA. After these and other giants of contemporary art, what's left in Barcelona's museum bag? Off the beaten track, down cobbled side streets and even smack bang in the middle of touristy areas, you'll find plenty of weird and wonderful little-known gems - all well worth an hour of your time.