Now that you've all exhausted the free Civil War resources at Ancestry.com, I'm happy to report another freebie. In honor of National Library Week, the Gale Press is offering free access to their databases. I'm not sure when a week turned into 14 days, but the free access is good from April 10th through April 24th, so there are a few days left to explore.
Just go to http://www.gale.cengage.com/NLW/ and scroll down to the database links. Of the 6 choices, I'm guessing those of most interest to SGS members will be the Gale News Vault, with over 10 million scanned and indexed pages, and the "Slavery and Anti-Slavery" archive.