IPython is a multiplatform, Free Software project (BSD licensed) that
offers:

* An enhanced Python shell designed for efficient interactive work. It
  includes many enhancements over the default Python shell, including the
  ability for controlling interactively all major GUI toolkits in a non-
  blocking manner.
* A library to build customized interactive environments using Python as
  the basic language (but with the possibility of having extended or
  alternate syntaxes).
* A system for interactive distributed and parallel computing (this is part
  of IPython's new development).