For those of you who use Adobe Photoshop on Windows, you may be looking forward to the new feature in the forthcoming CS5: Content-aware Fill. When I saw this announcement, it reminded me of a similar feature already present in GIMP on Linux: Liquid Rescale.
Not sure what this does? Take a look at some of the Examples. Liquid Rescale is very impressive, and has been around since about 2007. And it's dead simple to install on Linux. From the command line, as root, just type: yum install gimp-lqr-plugin. Or, you can install via the "Add/Remove Software" menu dialog.
GIMP stands for GNU Image Manipulation Program, and is a graphics program very similar to Photoshop. Most Linux distributions include GIMP.