Though they usually sell for about the same as shipping, if not a little less, I'd venture to say a Brownie Hawkeye Flash will make images that easily outstrip what you can get from most of the "toy camera" genre, and it's a lot more compact than most non-folding 6x6 -- in fact, it's close to being as small as a normal-lens 6x6 can get without folding. As a bonus, this model will usually accept trimmed 120 supply spools (mine doesn't even need them trimmed, but not all are this loose), and a brave soul could probably trim a little bakelite from the case, modify the winding key, and make it accept a 120 takeup spool as well. Hmmm...
Matter of fact, these cameras may have their price held down by the fact their images are *too* good (though surely being made for 620 contributes here); the Lomographic crowd don't want 'em unless they're mechanical enough to open them up and reverse the lens to get all kind of aberrations. For me, it's a nice, light, compact snapshooter. No focusing, no messing with exposure, just use the waist level finder to frame, and gently squeeze the release, good shot every time as long as there's enough light (and I've got a couple different flashes that fit mine, too, with bulbs).