If you like manipulating your photographs with filters after-the-fact, nothing is as awesome as Filter Forge. This stand alone program gives you access to over 10,000 filters (this is not an exaggeration), and any kind of effect you can imagine is at your fingertips. Kaleidoscopic patterns, chrome, watercolor treatments, etchings, shattered glass, and so much more. Within each filter, there are sliders that provide more variations than you can imagine. This is a truly brilliant program. It comes with some built-in filters, but there is a link in the dialog box that opens the door to thousands of filters than you can download for no extra charge.