The site covers:
congress-legislators: Detailed data on members of Congress, past and present.
congress: Scrapers and parsers for the work of Congress, all day, every day.
citation: Stand-alone legal citation detector. Text in, citations out.
uscode: Parser for the US Code.
bill-nicknames: Tiny spreadsheet of common nicknames for bills and laws.
glossary: A public domain glossary for the United States.
licensing: Policy guidelines for the licensing of US government information.
wish-list: Post ideas for new projects.
Eric has written a post explaining the project.