A report in the March, 1997 Journal of Clinical Investigation (pgs. 1158-1164) by  Dr. Alessio Fasano of the University of Maryland  shows how they are experimenting with using a protein called Zonula occludens toxin or Zot to make oral insulin feasible. Using Zot, researchers were able to significantly increase insulin transport across the intestines, and in diabetic rats at least were able to lower blood sugar levels to nearly normal levels.   Zot is derived from Vibrio cholera. Obviously with safety concerns and other problems it will be a while before diabetics can pop a pill.