If cells have a way of knowing where they are, then we should be able to get in there and confuse the heck out of them.
Dr. Michael Levin and his team at Tufts has done just that. As described in the paper Gap Junctional Blockade Stochastically Induces Different Species-Specific Head Anatomies in Genetically Wild-Type Girardia dorotocephala Flatworms, one can really confuse a flatworm fragment by disrupting certain aspects of its bioelectrical field. Specifically, if you cut off the head and tail of a flatworm, and then apply a certain chemical (octonal) to the fragment, the flatworm will regenerate with a head on both ends of its body.
The process whereby this happens is explained in great detail in the link above. As a model, CYCELL can replicate this phenomenon.
The video below demonstrates how the alteration of the cells' orientations by exposure to a certain substance (referred to as Levin-Juice in the video) can lead to a double-headed flatworm. Importantly, the double-headed-ness persists with subsequent amuptations even when the substance is no longer used.
(This video was made with a version of the downloadable program that has been tweaked somewhat... specifically, we added the ability to 'pause' mitosis as well as a command to apply the octonal. So, regretably, you won't be able to reproduce this with the current version. But, we might add some features in a future version, so check back now and then.)