A quick way to set the ICON for a folder or application in MAC OS X is by clicking cmd-I once on the file/app you want to set the new icon and once on the folder you want to get-from the icon, and then copy the very-top icon (not preview) vice-versa with cmd+c and cmd+v
But what if you have just downloaded a great icon and it’s not a folder (no icon to copy when you press cmd-i) but it’s in .icns raw-icon format? Then you need IconDroplet (http://www.macupdate.com/info.php/id/19771)
IconDroplet is an AppleScript Droplet that takes raw icon files (*.icns) and turns them into files that are embedded with the icon. After the files are processed you can "Get Info" (cmd-i) on the resulting files and copy/paste the icons to other items!!!!
