I recently picked up the Polaroid Captiva SLR and Polaroid Joy cameras from e-bay.com. Both were released and available from Polaroid 1993–1997.
The Captiva and Joy use the no-longer-manufactured Polaroid 500 Instant film.
Polaroid Type 500 film (produced from 1993-2005) has an image size of 73x54mm ( 2.874 x 2.126 inches), is ISO 600 and has 10 pictures to a pack.
My initial experience is that most existing packs available today have been improperly stored, causing the internal chemicals to dry out. The result causes film packs to leak caustic chemicals upon firing the shutter, malfunction or failure to eject any image at all.
One of the packs exposed through the Captiva camera yielded some decent images (above).
Existing, expired film packs are scarce. When available these film packs can fetch upwards of $20. - $50. each on ebay.
Further testing and experimentation as soon as I can locate more film packs
All Images © 2010 Michael Raso unless otherwise noted.