The team at FastCase has announced the largest free online US case law database at The Public Library of Law at plol.org. The site is GREAT! The database of cases includes all of the Supreme Court cases and US Court of Appeals cases since 1950 (the same data FastCase recently presented to the Legal Commons project) AND US state case law since 1997 for all 50 states in nice standardized searchable, and usable html format for all states (not the random state by state format many other sites have collected the data in).
In addition to the case law, the The Public Library of Law also has online or links to the codes and statutes, constitutions and regulations of the Federal Government and all 50 US state governments.
Peace,
Tim