A Visual Thesaurus post by Ben Zimmer is an interesting exploration of the history of a great word, scalawag:
My latest column for the Boston Globe tells how Nathaniel Sharpe, a 22-year-old amateur genealogist from a small town in North Dakota near the border with Canada, discovered some keys to the origins of scalawag when he found that one of his ancestors was described with that label. Actually, he was called a skallewagg (one of many variant spellings floating around), in an 1836 newspaper from Batavia, New York that printed a list of people who had skipped town before settling their debts with local merchants.
Sharpe found the article on FultonHistory.com, a rather quirky website that archives digitized newspapers from New York State. He kept looking in the Batavia papers for other listings of debtors, and managed to take skallewagg back to the Sep. 16, 1834 issue of the Batavia Republican Advocate, following the name of Abial Hawkins, a butcher. Further digging on another database turned up scalliwag in a political context in 1832, referring to opponents of the region's Anti-Masonic Party.
The whole thing is a lot of fun, and hurray for quirky websites like FultonHistory.com.
Incidentally, if you like reading about books, occasional LH commenter Gou Tongzhi has a site Book Solo, well described by its subtitle: "One man tries to read everything." He's got reviews going back twenty years.