Instructables contributor Jessyratfink posted plans to build this wonderful Barbie Doll Electric Chair. She writes:
This is a science fair project that I did in middle school and completely disgusted the entire female staff of Benton Middle. The purpose of this project is to show how the electric chair works and discuss basic electricity - currents and conductivity.Link
This is perhaps not the most politically correct science fair project, but it definitely gets attention. And although it is more based on presentation than science, most people find it very interesting to learn how an electric chair works.