Seam Carving
I totally happened upon seam carving by total accident, which of course means that it has to be cool; I mean we hardly find the coolest stuff when we mean to… or is it just my luck?
Anyways, seam carving is a process that alters the dimensions of an image by intelligently removing pixels, or adding pixels to the image by way of an algorithm that determines which pixels carry little importance. There is a full whitepaper to read and a video demo. Acknowledgment goes to Shai Avidan and Ariel Shamir whom developed the alogrithm and presented at SIGGRAPH 2007.