The authors would like to thank Ali Azarbayejani, Baback Moghaddam, and Kenneth Russell for providing access to their 3D shape recovery, face recognition, and graphics code respectively. Thanks also to Michal Hlavac for his deft skill in 3D modeling and Fred Martin and Rob Poor for their IR transponder designs. Last, but certainly not least, thanks to Tavenner Hall for her constructive criticism and proofing early copies of this document.