Jython Console with Code Completion
http://code.google.com/p/jythonconsole/
Download jythonconsole-0.0.4.zip from Google Code page.
jythonconsole-0.0.4.zip
Extract the archive. I extracted to:
C:\tools\jythonconsole-0.0.4\
jython \tools\jythonconsole-0.0.4\console.py