The following databases are available free this week (some longer):

• Index to Foreign Legal Periodicals - Ovid actually offers a free database every month - See their Resource of the Month page
• ebrary is offering complimentary access to library science e-books for a full year.
• Gale is offering access to a vast number of databases in areas such as history, health, nursing, science, literature, reference, and readers advisory, etc.
• Greenwood Publishing is also offering a number of databases in cultures, history, reference, and readers advisory.
• OECD.stat (statistical publications) is available for free for the first half of 2008 while it's still in Beta.
• Legal Dockets Online - login: nlw; password: free

Source: AbsTracked and my colleague, Nancy Paul