WebKit now supports styling of the scrollbars in overflow sections, listboxes, dropdown menus and textareas. The scrollbar pseudo-element indicates that an object should use a custom scrollbar. When this pseudo element is present, WebKit will turn off its built-in scrollbar rendering and just use the information provided in CSS. The screenshot is generated with following CSS:

::-webkit-scrollbar {
    width: 13px;
    height: 13px;
}

More info: Styling Scrollbars

Source:→ Ajaxian