The Hammurabi Project is an experiment in codifying U.S. law - such as the U.S. Code, the Code of Federal Regulations, state laws, etc. - in a machine-executable format.
There are millions of pages of law with which Americans are expected to comply.
And though the law is massive and complicated, it is in many ways computational, specifying algorithms to be carried out, like: What is my standard (tax) deduction? Am I eligible for family and medical leave? On what day did I become liable for unemployment taxes?
Determinations such as these weave together into a vast network of rules, which can be compiled and embedded into our computing infrastructure to drive other software applications.
More information can be found on the project wiki.