se guardi il codice del box (io uso firebug) vedi questo
[cede]
<div id="twitterFollowBadge"><div style="background: rgb(182, 9, 11) url(http://files.go2web20.net/twitterbad.../follow-me.png) no-repeat scroll left top; position: fixed; top: 150px; width: 30px; height: 119px; z-index: 8765; cursor: pointer; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous; right: 0pt;" id="tfbTab"/><div style="background: transparent url(http://files.go2web20.net/twitterbad...icon-about.png) no-repeat scroll 0% 0%; position: absolute; top: 243px; width: 10px; height: 11px; z-index: 9876; cursor: pointer; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous; right: 0pt;" id="tfbAbout"/><style>#tfbAbout{visibility:hidden;} #twitterFollowBadge:hover #tfbAbout{visibility:visible;}</style></div>
[/code]

la posizione fissa lascia l'elemento li dove indichi con le coordinate (top left.....)