Fancy Scroller Start.

gistfile1.js

// TODO: Encaps this and fancyScroll in function.
var currentObj = null;
var fancyScrolling = false;

function fancyScroll(ev, down) {
    var scrollToOffset = 60,
        scrollDuration = 500;

    // Do nothing if we're already animating.
    if (!$('body').is(':animated')) {
        var windowHeight = $(window).height(),
            bottomThreshold = 0, // Same as navbar height.
            objToScroll = null,
            lastBottom = down && -1 || 9999999;

        // Check all the sections and determine if we're scrolling in to one.
        $("section, header").each(function () {
            var elTop = this.getBoundingClientRect().top,
                elBottom = this.getBoundingClientRect().bottom;

            if (windowHeight - elTop > 0 && elBottom > bottomThreshold) {
                if ((down && elBottom > lastBottom) ||
                    (!down && elBottom < lastBottom) {
                    objToScroll = this.id;
                    lastBottom = elBottom;
                }
            }
        });

        if (objToScroll !== currentObj) {
            // Do Fancy Scrolling
            fancyScrolling = true;

            $('html, body').stop();

            $('body').animate({
                scrollTop: $("#" + objToScroll).offset().top + scrollToOffset
            }, {
                duration: scrollDuration,
                complete: function () {
                    fancyScrolling = false;
                },
                easing: 'easeInOutExpo'
            });

            currentObj = objToScroll;
        }
    }
}

$(window).bind('mousewheel', function(e){
    if(e.originalEvent.wheelDelta /120 > 0) {
        $('body').stop();
    }
    else{
        $('body').stop();
    }
});

$(window).keydown(function (ev) {
    if (ev.keyCode === 38 ||    // Up
        ev.keyCode === 40 ||    // Down
        ev.keyCode === 33 ||    // Page-Up
        ev.keyCode === 34) {    // Page-Down
        $('body').stop();
    }
});

var lastScrollTop = 0;


$(window).scroll(function (ev) {
    // contrib: http://stackoverflow.com/a/4326907
    var st = $(this).scrollTop();

    if (st > lastScrollTop){
        checkNavbar();
        fancyScroll(ev, true);
    } else {
        checkNavbar();
        fancyScroll(ev, false);
    }
    lastScrollTop = st;
});