DHTML popup help window

I'm looking for something like

http://www.richercomponents.com/richhelptip/demos/0/
(Click the ? next to the text box)

I would like to have a window appear on the screen when the user clicks
a help button. The window would need to be positioned next to the help
button and have a close link.

I looked that the JS created by the richercomponents page, and it seems
really really heavy for what I need. Are there any suggestions. I think
this is just a div tag that is hidden but I have no idea how to do the
positioning.

Thanks
Robin