The ODB is a free repository for open data. The data here is available without charge, license, or restrictions. All of the data is available in a variety of open formats, including HTML, XML, CSV, JSON, RDF, and tab-delimited text.
Warning: This site is in its earliest stages, so it's likely there are large pieces of it that don't work properly.
Data looks fairly miscellaneous and includes:
United States Presidents
Nothing explicit but have the open data button the site.