SensusAccess is a tool that converts documents into a range of alternative formats including digital Braille, MP3, DAISY and e-books. The service can also be used to convert otherwise inaccessible documents such as image-only PDF files or scanned images into more accessible formats.
SensusAccess is intended as a self-service solution for print-impaired students, faculty and alumni at universities and colleges, and complements the accessibility services usually offered by educational institutions. The service can also be used by faculty to convert lecture notes and other educational material into accessible formats.
You can read more about the service here, or view a conversion file matrix to see which file types are supported. Note: While SensusAccess supports a variety of languages, at the moment it does not support language-to-language translation. In other words, the source file and the converted file need to be in the same language. (They are apparently considering adding this feature.)