A photo of flower pots at a vendor's stall provided the source image here.  Many manipulations were applied, including Waves, Flows, Vortices, Melts and Bubbles.  Then the Wipe Tool was dragged across the entire image to cause the source image to partially show through, half normally and half with negative colors.  Actually, this example illustrates how the Scripting feature might be a useful tool for digital artists.  After deciding that the picture had some potential, the Append History to Recorded option was used to save the creation steps as a Recorded Sequence.  The Script Editing screen was then used to experiment with how altering various parameters affected the results, including spliting the final Wipe into 2 steps, one using the Transparency Wipe Action and the other the Negate Colors Wipe Action.  Finally the Image Load action was changed to select a large source image (2048 x 1536), and after the Script was played back Upscale was used to render the picture at 2048 x 1536 size.  That was copied and pasted into a graphics program, and rescaled to this 800 x 600 image.