Gazou-wo-purupuru-ni-suru-soft (A software to make image puddingy) is a tentative tool developed in C++ language by a Nico Nico Douga user YNW. You see how it works here, (you may turn off Japanese comments by the bottom-right button)
# I cannot watch the movie above from Taipei hotel now but should be okay. If your browser doesn’t go you need to go to the original page which requires Nico Nico Douga registration.
On the tool, you direct regions to move and give parameters how much it bound with area around, how it is bounced. Then dragging the image will make natural(?) movement physically calculated.
Version 3.0 and its demo was released.
The tool download page [J] – you need a password written on the original Nico Nico Douga page’s description
[Update 2012-06-21] new version 3.x download page