<a class="bubbled"> Mouse over me! <span class="arrow arrow-left-top hide">message in the bubble</span> </a>
.bubbled: class to the element containing the tooltips
.arrow: this class will create the box and the hover behaviour of the box
.arrow-left-top: this class will create the arrow of the box at the place you choosed.
.hide: this will hide the arrow box element, the box will appear only on over