Powershell ISE!

A graphical user interface and script editor for Microsoft Windows PowerShell .

PowerShell Studio is the easiest GUI designer and script generator available. It is the most powerful PowerShell ISE available, generates the Windows Forms code and allows remote debugging!

win-bash is a Windows port of the famous GNU bash (see GNU Bash homepage).

PowerShell Plus is an Integrated Scripting Environment (ISE) which includes unique features like an interactive learning center, hundreds of pre-loaded scripts from the QuickClick Library, and other useful features.