When I get 12exp rolls of film, half frame is the logical way to get the most out of them. So when I came across some expired but nice AGFA Portrait 160, I slotted it straight into my Pen D3.
I bought this camera in Japan last month in a tiny camera shop in the basement of a karaoke club in Shinjuku. It's probably the most advanced Pen aside from the F series, sporting a CdS light meter and a fast f1.7 lens. I always get a few light leaks at one end of the roll for some reason, but in this case I like them.