There are lots of Haskell-related projects that are exciting but also not ready yet and so people mostly don't know about them. When something becomes widely known it should be removed from this list.
HyperHaskell is a graphical interpreter for the programming language Haskell. You use worksheets to enter expressions and evaluate them. Results are displayed using HTML.
HyperHaskell uses the GHC API to interpret Haskell programs. The graphical front-end is built on the cross-platform Electron framework.
A new graphical Haskell interpreter, looks similar to IHaskell.