This little store offers a good selection of all-Icelandic t-shirts and sweaters with some funny Icelandic slogans. The shop also have some silly items, such as a squirt camera and some bacon lip balms.
Many tourists enjoy these kinds of souvenirs rather than the basic stuffed up puffin. If you want a cool and funny thing to show to your friends back at home, then give this a shot.
If you don't get the jokes on the t-shirt, ask the salesman to explain. If you do understand, ask him anyway just for the fun of it.