Some [hopefully] useful extensions to Ruby’s String class. It is made up of three libraries: ActsAsUrl [permalink solution with better character translation], Unidecoder [Unicode to Ascii transliteration], and StringExtensions [miscellaneous helper methods for the String class].
Line 169 (x03A7) is the Unicode code point capital chi 'Χ'. The transliteration should 'X' rather than 'Ks' to be consistent with lower case version at line 201 (x03C7). http://en.wikipedia.org/wiki/Greek_alphabet#Greek_in_Unicode