Sean Leather presents his `xformat` library for extensible and type safe formatting at the Dutch Haskell User Group meeting in September 2009.
Blog post (including slides): splonderzoek.blogspot.com/2009/09/extensibility-and-type-safety-in.html
Library on Hackage: hackage.haskell.org/package/xformat
Dutch HUG website: dutchhug.nl
Dutch HUG mailing list: groups.google.com/group/dutch-hug