Simple debounce function bases on underscore's.

gistfile1.coffee

App.debounce = (func, wait) ->
  timeout = null

  ->
    context = this
    args = arguments

    immediate = true if args[0] and args[0].now

    later = ->
      timeout = null
      func.apply(context, args)

    clearTimeout(timeout)

    if immediate
      func.apply(context, args)
    else
      timeout = setTimeout(later, wait)