This basically just transposes all alphabetic characters in a string up 13 places, as implied by the name ROTation-13. Its really simple, but still fun. Enjoy. MsgBox(0, "HELLO:", ROT13("HELLO:"));Returns "URYYB:" Func ROT13($String) $Letters = StringSplit($String, "") Local $Result = "" For $a = 1 to $Letters[0] $Char = TransChr($Letters[$a]) $Result&=$Char Next Return $Result EndFunc Func TransChr($Chr) If StringRegExp($Chr, "[a-z]") Then $Lower = StringSplit("abcdefghi