I’ve recently bought a Diana Mini, a Lomography camera which is plastic and very very small. It takes either 24mm x 24mm square photos or half-frame photos. It is also very handy for taking multiple exposure shots with, as the shutter is mostly independent of the film winder.
Diana Mini, Agfa Vista Plus 200.
(there are more of my photos on my photo blog thing at mostlytrees.wordpress.com)