A few years back, the new thing in little prime lenses was the pancake lens. These super-compact prime lenses were, and still are, pretty affordable, and they appeal to photographers who want to shoot with wide-to-normal primes that are super compact and keep the camera’s size and weight to a minimum. Well now the next big thing in little lenses is the body cap with the lens built in. Taking a cue from the folks who turn their DSLRs into pinhole cameras via the body cap, two new lenses from Olympus and Pentax set new standards for small size and low price. There’s the Pentax Mount Shield Lens (for Q-mount cameras) which produces a dreamy, low-fi effect. And there’s the Olympus Body Cap Lens, a tiny 3-element 15mm lens with a fixed aperture (it fits Micro Four Thirds cameras). These "lenses" are inexpensive ($49 for the Olympus, $79 for the Pentax) which makes me wonder if they actually produce anything useful. But I’ve seen samples, and while they’re not on par with real expensive lenses, they’re no joke. The more I think about it, these things are super-inexpensive for lenses, but pretty darn expensive for plain old body caps. If you’ve played with a body cap lens, I’d love to have you chime in via the comments below. Should we all pack one of these things, or would we be better served by some other quirky photographic accessory? I’m intrigued.