Findlaw Legal Research: Government offices, cases, statutes, bar associations, and legal forms
LII (The Legal Information Institute): A comprehensive legal resource run by Cornell University Law School. Contains substantial holdings of federal statutes, regulations, and decisions including the U.S. Code and Code of Federal Regulations (CFR). Contains materials on virtually all areas of substantive law along with significant holdings and links to state law materials, including the UCC. A resource for law students (with links to U.S. law schools) as well as practitioners (with links to professional resources).
Lexis Legal Research: A free legal research site for cases, statutes, and legal forms