I'd say xmonad[1]! It is a very light and fast tiling WM.

There's also a couple of elegant and blazingly fast web frameworks, such as Yesod, Snap and Happstack[2].

1: http://xmonad.org/

2: http://www.haskell.org/haskellwiki/Web/Comparison_of_Happsta... http://stackoverflow.com/questions/5645168/comparing-haskell...

Installing xmonad requires several hundred megs of dependencies, so what does it mean for it to be light? Low memory footprint?

Pretty much. Hard disk space is still cheaper than RAM, so I think it's a good tradeoff. Plus those dependencies can be used for lots of other things.

Pandoc:

http://johnmacfarlane.net/pandoc/

XMonad:

http://xmonad.org/

Well, xmonad is an excellent example :-)