Google Scholar has added full text searching of caselaw and legal journals. Just go to scholar.google.com and choose the "Legal Opinions and Journals" radio button. You can also use the advanced search feature to limit your search by jurisdiction.
In addition to the text of the case, Google Scholar offers a nice looking "How Cited" feature that shows how the case has been cited and provides a list of citing cases and related documents.
Many bloggers have already expressed excitement about this development and are naturally wondering how this will affect Westlaw/Lexis products. Read more about it here,
here and here.
Ernster, the Virtual Library Cat
Above the Law - A Legal Tabloid - News, Gossip, and Colorful Commentary on Law Firms and the Legal Profession