<script language="JavaScript1.2"> /* DHTML Announcement Box- By Jim Silver @ jimsilver47@yahoo.com Exlusive permission granted to Dynamic Drive (http://dynamicdrive.com) to include this script in their DHTML archive. For full source code, terms of use, and 100's more scripts, visit http://dynamicdrive.com */ //drag drop function for NS 4//// ///////////////////////////////// var dragswitch=0 var nsx var nsy var nstemp function drag_dropns(name){ temp=eval(name) temp.captureEvents(Event.MOUSEDOWN | Event.MOUSEUP) temp.onmousedown=gons temp.onmousemove=dragns temp.onmouseup=stopns } function gons(e){ temp.captureEvents(Event.MOUSEMOVE) nsx=e.x nsy=e.y } function dragns(e){ if (dragswitch==1){ temp.moveBy(e.x-nsx,e.y-nsy) return false } } function stopns(){ temp.releaseEvents(Event.MOUSEMOVE) } //drag drop function for IE 4+//// ///////////////////////////////// var dragapproved=false function drag_dropie(){ if (dragapproved==true){ document.all.showimage.style.pixelLeft=tempx+event.clientX-iex document.all.showimage.style.pixelTop=tempy+event.clientY-iey return false } } function initializedragie(){ iex=event.clientX iey=event.clientY tempx=showimage.style.pixelLeft tempy=showimage.style.pixelTop dragapproved=true document.onmousemove=drag_dropie } if (document.all){ document.onmouseup=new Function("dragapproved=false") } ////drag drop functions end here////// function hidebox(){ if (document.all) showimage.style.visibility="hidden" else if (document.layers) document.showimage.visibility="hide" } </script>

Coloque dentro do body

<div id="showimage" style="position: absolute; width: 145; left: 274; top: 51; height: 46"> <table border="0" width="100%" height="100%"bgcolor="black" cellpadding="2"> <tr> <td width="100%" height="100%"> <table border="0" width="100%" height="100%" cellspacing="0" cellpadding="0"> <tr> <td onMousedown="initializedragie()" style="cursor:hand" height="11"><ilayer width="100%" onSelectStart="return false"> <layer width="100%" onMouseover="dragswitch=1;drag_dropns(showimage)" onMouseout="dragswitch=0"> <p align="center"><font face="Verdana" color=white><strong><small> MURAL DE AVISOS </small></strong></font></p> </layer> </td> <td style="cursor:hand" height="11"> <p align="right"><a href="#" onClick="hidebox();return false"> <img src="fechar.gif" border="0" alt="Feche essa janela" width="11" height="11"></a></td> </tr> <tr> <td bgcolor=#FFFFFF style="padding:1px" colspan="2" valign="top" align="justify"> <p align="center"> <font face="Verdana">Seu texto aqui </font></td> </tr> </table> </td> </tr> </table> </div>

Você pode mudar a cor e o tamanho.
Você precisará da imagem fechar.gif.
Copie a imagem pra pesma pasta onde está a página que contém o
mural de avisos.