Pivotal prototype uses Gtk2Hs
Keith Hanna is reworking his interactive, document-centered Haskell environment Vital in Haskell. The project is now called Pivotal and is written entirely in Haskell, using Gtk2Hs for the GUI. The idea of the project is to have an interactive environment like a spreadsheet, but instead of entering untyped formulae over very basic types, all elements of the spreadsheet are well-typed Haskell expressions. This does not only give type-safety, but also allows for much more interesting data types like trees or even pictures. Check out the home page for some stunning examples!