I was playing around with my Polaroid Camera a while back. Looking at the negative you get after you pull the Polaroid off looks cooler than the Polaroid itself! So I took a couple of shots of it and put it together to make a border for any other HDR pic I thought might look cool in it. Check it out! Oh it is also available for download at my MediaFire site as a Photoshop .PSD file.
It is pretty simple to use the template , just put your Picture above Layer 1, re-size it to fit, then duplicate it, invert the duplicate, and set the duplicate blending mode to Overlay. Now you can flatten it and be on your way. It isn’t a true “Negative” per-say but it makes the picture look pretty cool.