Definitely! It's really cool stuff. But something like that for real Haskell (e.g. GHC) would be even better :) I could be an offline downloadable application. It would be a very nice tool: create postscript (or PDF, or LaTex, whatever rich text format) documents with Haskell "boxes" inside. Real literate programming... Oh well ;)
I would personally say Haskell 98 is "real" Haskell (well, until Haskell Prime comes out). It becomes difficult for tool developers to cater for non-standard languages; Haskell is quite complicated enough without having to cater for all the little nuances and idiomatic extensions that are constantly added with each release of a compiler. I believe it does work as an offline downloadable tool... http://www.cs.kent.ac.uk/projects/vital/install/index.html Chris.