The Law Library of Congress this week unveiled a Web archive of legal blogs. The library began archiving selected legal blogs in 2007 and now has archives for more than 100 blogs covering a range of legal topics.
It appears to me that these archives are periodic snapshots of each blog rather than complete collections of the blog’s posts. From this page, the collection can be browsed by subject, blog title and author name. The page also provides searching, but only of the blog’s bibliographic information, not its full text.