Operating Systems

House
Haskell User's Operating System and Environment, demo of software, runs standalone; can be a platform to explore ideas in low- and system-level programming in high-level functional languages. Based on hOp Haskell, a variant of GHC Haskell.
http://programatica.cs.pdx.edu/House/

A Principled Approach to Operating System Construction in Haskell
Research paper on monadic interface to low-level hardware features that are useful basis for building operating systems in Haskell; has primitives to control memory management hardware, user-mode process execution, low-level device I/O. Abstract; PDF, PS.
http://ogi.altocumulus.org/~hallgren/ICFP2005/

Wikipedia: House Operating System
Encyclopedia article, with links to many related topics.
http://en.wikipedia.org/wiki/House_(operating_system)