jquery whole page/window slider

I'm interested in making a whole page slider like in http://littlemonsters.com/ for example. I've looked around at their code and am trying to figure out

-how they did this whole page slide (which I guess is just a very big slider), and also

-how although the individual 'pages' are stacked on top of each other (like a normal page), when they slide, they are sliding left and right (part of the whole slider problem I guess)

It seems that for many slider plugins, they somehow horizontalize list items (whereas when I do sliders by hand I make a really really long wide list with like width 9999px and have an overflow hidden viewing window--this is probably not the best way). here's some js I found on the above site that I think holds the key but I can't understand too well/incomplete.

step = (id) ->

  width = $(window).width()

  dir = 1

  dir = -1  if id < curId

  curId = id

  $(".boxDisplay").animate

    left: -1 * dir * width

  , 500, "swing", ->

    $(this).css "left", 0

    $(this).removeClass "boxDisplay"

    next = $(".box:eq(" + (id - 1) + ")")

    next.addClass "boxDisplay"

    boxPosition()

    next.css "left", dir * width

    next.animate

      left: 0

    , 500, "swing"

animate = ->

  i = 0

  $(".box").animate(

    left: -50

  , 10).animate(

    left: 0

  , 50).animate(

    left: 50

  , 10).animate(

    left: 0

  , 50).animate(

    left: -25

  , 10).animate(

    left: 0

  , 50).animate(

    left: 25

  , 10).animate(

    left: 0

  , 50).animate

    left: 0

  , 800

boxPosition = ->

  height = $(".boxDisplay").height()

  $(".box").css "margin-top", ($(window).height() / 2) - (height / 2)



$(document).ready ->

  boxPosition()

Thanks!