DocDiff compares two text files and shows the difference. It can compare files
word by word, character by character, or line by line. It has several output
formats such as HTML, tty, Manued, or user-defined markup.

It supports several encodings and end-of-line characters, including ASCII (and
other single byte encodings such as ISO-8859-*), UTF-8, EUC-JP, Shift_JIS, CR,
LF, and CRLF.

WWW: http://docdiff.sourceforge.net/