gistfile1

/*jslint browser: true*/
(function () {
    "use strict";
    var d = document,
        a = document.createElement('div'),
        i = 0,
        e = '1px solid #a0a',
        f,
        g,
        b,
        c,
        z;
    z = function (i, x, y) {
        return function () {
            var id = 'Ͼ' + i,
                b,
                t;
            c = (i * 2);
            b = d.getElementById(id);
            f = parseInt(Math.sin(c) * 100, 10);

            t = (f + y) + 'px';

            if (!b) {
                b = a.cloneNode(true);
                b.id = id;
                f = f > 0 ? f : -f;
                f = f.toString(16);
                g = f.length;
                while (g++ < 6) {
                    f = '0' + f;
                }
                b.style.background = "#" + f;
            }
            b.style.left = (c * 2 + x) + 'px';
            b.style.top = t;
            d.body.appendChild(b);
        }
    };
    a.style.position = "absolute";
    a.style.width = "10px";
    a.style.height = "10px";
    a.style.borderRadius = "10px";
    a.style.boxShadow = "2px 2px 2px #000";
    a.style.borderTop = e;
    a.style.borderLeft = e;
    document.onmousemove = function (e) {
        var i;
        for (i = 0; i < 30; i += 1) {
            setTimeout(z(i, e.pageX, e.pageY), 10 * i + 10);
        }
    };
}());