Zenity

Only of interest if you're using Linux, and then only if you're using Gnome.

Zenity is a really cool way of generating graphical output from simple shell scripts.

Ever wondered how people get all those lovely dialogue boxes?

Well Zenity (or KDialog if you're using KDE) is the answer.

They both usually come with you're favourite distribution - if they are not installed try your repository. Else Goole the name.