In the upper left corner would be a small icon to represent the image choice used on the front of the postcard (could be the image itself smaller or even the users profile icon) alongside a short copy blurb with the title, a short and sweet description of the image underscoring how many user contributions led to the collaborated image.

Oops! Uploaded the wrong one, this should have RECrobot (acrylic on canvas) @annejumps  for its little blurb on the back, but you can get the basic idea here.

Just a rough concept.

There is a 1/4 inch bleed on this that should be cropped off for mock-ups/reMIXes ;^)

In the upper left corner would be a small icon to represent the image choice used on the front of the postcard (could be the image itself smaller or even the users profile icon) alongside a short copy blurb with the title, a short and sweet description of the image underscoring how many user contributions led to the collaborated image.

More postcard ideas here - http://www.hitrecord.org/records/572533

I really couldn't help myself.

A couple of silly ones are a must, right?