Perl module to get context around a keyword

 Text::Context::EitherSide is a Perl module that extracts some context from a
 large piece of text, such as a web page or mail message. You can search for a
 keyword and intelligently get some context in which you found the keywords
 inside the body of the text. It is more rigorous than simply extracting the
 two words on either side of each keyword, since multiple searches may have
 overlapping context.