Buy 'em by the bagful. Pocket Instamatics are the coolest shoot-from-the-hip Lomographic junk store cameras. Now you can reload them with regular 35mm film.
All you need is a film slitter to slice the film down to 110 size. Easy, cheap, and quick to make. See my Instamatic Film Slitter
110 film is hard to get except from The Frugal Photographer
. This is a great source for other hard to find film as well.
Most photo lab chains can develop, but not print, 110 film for under $2 USD a roll.
Or for developing and prints, you can use York Photo
for about $4 USD a roll.
Submini cameras need to be very steady. You will get sharper photos if you prop the camera against a wall, tree, or car, or use a pocket tripod
if the camera has tripod socket.