I don't remember exactly how I discovered Patrick Winfield's Composites, but his multi-Polaroid sans-frame pieces inspired me to try to isolate some of my images from the standard white border. Upon incorporating these de-framed Polaroids into collage cards, I have created something that isn't likely to be immediately recognized as a Polaroid, but has an interesting appeal nonetheless.
Removing the frame isn't quite as complicated as you might think. Simply finding a loose edge or corner and peeling is all that the process really requires - as long as you're careful not to rip the actual photograph, your image should be fine.
Here are a few of my results!