From Anthony Goubard:
Japplis Toolbox is a compilation of text utilities in one application. It can encode and decode URL, Base64, Hex, SoundEx or Metaphone. It can convert numbers from/to binary, octal, decimal, hexadecimal and to date. It gives you text information such as character count, word count, MD5 or SHA. You can get Java system properties, environment variables or Swing default values. You can run it online as Applet.