I was browsing flickr and came across images, which led to a link to the Poladroid site.
It is a fantastic new application that coverts your JPEG images to polaroids at 400dpi actual size. It uses a filter to create a colour cast, vignette and blur. Since poplaroid film is no longer being made it is a greta way to fake the effects of a polaroid. It even gives you the texture of the paper!
Just like a real polaroid you can only take 10 photos, before you have to relaunch the software. It is a simple drag and drop process and it even develops as you watch.
I have found it very addictive. You can download it free of charge for both the Mac and the PC here. http://www.poladroid.net/
Have fun. Here are some of my photos.