ImageJ macro for generating de Mariano Rajoy hybrid image at http://www.flickr.com/photos/rinzewind/9458528864/.

mariano.ijm

open("C:\\temp\\barcenas.tif");
run("32-bit");
run("Mean...", "radius=30");
open("C:\\temp\\mariano.tif");
run("32-bit");
run("Duplicate...", "title=mariano-1.tif");
run("Mean...", "radius=20");
imageCalculator("Subtract create 32-bit", "mariano.tif","mariano-1.tif");
imageCalculator("Add create 32-bit", "Result of mariano.tif","barcenas.tif");
selectWindow("barcenas.tif");
close();
selectWindow("mariano.tif");
close();
selectWindow("mariano-1.tif");
close();
selectWindow("Result of mariano.tif");
close();
selectWindow("Result of Result of mariano.tif");
makeRectangle(504, 72, 1600, 2132);
run("Copy");
run("Internal Clipboard");
run("Out [-]");
selectWindow("Result of Result of mariano.tif");
close();