I had quite a few polaroids that were never getting used. Main reason is that I do not quite like the film, don't care about the instant result, it does not give me a negative to enlarge, ... Also, the film packs are expensive at the shop I go to (where I buy my other films).
However, I have a lot of respect for the cameras themselve, and quite enjoy just shooting them without film in it. Ofcourse my family started thinking I was crazy (who can blame them?).
So I did what every toycamera user would do: I went to the garage to get my saw The result can be seen here: a polaroid instant 20 with a 120 rollfilm back. The back is removeable (even during a roll by using the dark slide), so running out of batteries is not a problem (batteries are on the inside of the camera...). I cut away a bit of plastic at various locations but I think the camera would still function correctly when the back is removed and polaroid film is inserted.
Now I just need some more spare time to go out and shoot with it...
Also, I'd like to note that I am not the first to do this (but I was amazed I couldn't find more info on it all over the net). Here is the only example of anything coming close to it: http://www.xs4all.nl/~hkeijser/camer...eras.main.html . Seems like his modifications were more destructive, but his results do look promising!