The objects appear to be walking, but after closer inspection, you will see it is all an illusion.
A demo of my program, which can be found here: http://www.openprocessing.org/sketch/179949
Or on my blog along with this video here: http://criticaltinkerer.blogspot.com/2015/01/footsteps-and-kickback-illusions.html
Stuart Anstis' original paper presenting the footsteps illusion is here: http://anstislab.ucsd.edu/files/2012/11/2003-Moving-objects-appear-to-slow-down-at-low-contrasts.pdf
And the one with the kickback and others is here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2637218/