How can I create a “tooltip tail” using pure CSS?

Here’s an example with a box-shadow, all latest version browsers should support this

http://jsfiddle.net/MZXCj/1/

HTML:

<div id="toolTip">
    <p>i can haz css tooltip</p>
    <div id="tailShadow"></div>
    <div id="tail1"></div>
    <div id="tail2"></div>
</div>

CSS:

body {font-family:Helvetica,Arial,sans-serif;}

#toolTip {
    position:relative;
}

#toolTip p {
    padding:10px;
    background-color:#f9f9f9;
    border:solid 1px #a0c7ff;
    -moz-border-radius:5px;-ie-border-radius:5px;-webkit-border-radius:5px;-o-border-radius:5px;border-radius:5px;
}

#tailShadow {
    position:absolute;
    bottom:-8px;
    left:28px;
    width:0;height:0;
    border:solid 2px #fff;
    box-shadow:0 0 10px 1px #555;
}

#tail1 {
    position:absolute;
    bottom:-20px;
    left:20px;
    width:0;height:0;
    border-color:#a0c7ff transparent transparent transparent;
    border-width:10px;
    border-style:solid;
}

#tail2 {
    position:absolute;
    bottom:-18px;
    left:20px;
    width:0;height:0;
    border-color:#f9f9f9 transparent transparent transparent;
    border-width:10px;
    border-style:solid;
}

body {
  font-family: Helvetica, Arial, sans-serif;
}
#toolTip {
  position: relative;
}
#toolTip p {
  padding: 10px;
  background-color: #f9f9f9;
  border: solid 1px #a0c7ff;
  -moz-border-radius: 5px;
  -ie-border-radius: 5px;
  -webkit-border-radius: 5px;
  -o-border-radius: 5px;
  border-radius: 5px;
}
#tailShadow {
  position: absolute;
  bottom: -8px;
  left: 28px;
  width: 0;
  height: 0;
  border: solid 2px #fff;
  box-shadow: 0 0 10px 1px #555;
}
#tail1 {
  position: absolute;
  bottom: -20px;
  left: 20px;
  width: 0;
  height: 0;
  border-color: #a0c7ff transparent transparent transparent;
  border-width: 10px;
  border-style: solid;
}
#tail2 {
  position: absolute;
  bottom: -18px;
  left: 20px;
  width: 0;
  height: 0;
  border-color: #f9f9f9 transparent transparent transparent;
  border-width: 10px;
  border-style: solid;
}

<div id="toolTip">
  <p>i can haz css tooltip</p>
  <div id="tailShadow"></div>
  <div id="tail1"></div>
  <div id="tail2"></div>
</div>