the largest free law library in the world, law available for free scattered across many different sites -- all in one place. U.S. Supreme Court and Courts of Appeals. all 50 states back to 1997. Federal statutory law and codes from all 50 states. Regulations, court rules, constitutions, and more!
Justia you follow cases of interest for free, and publishes some case files online. Justia's working with Cornell University to throw some Web 2.0 tools into the mix, including wiki pages for decisions, automated tracking of citations to decisions, and tools to track what briefs a particular attorney has written.