<SCRIPT LANGUAGE="JavaScript">
var initialsubj="Hay buddy, take a look at this"
var initialmsg="Hi:\n You may want to check out this site: "+window.location
var good;

function checkEmailAddress(field)
{
  var goodEmail = field.value.match(/^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-]{2,})+\.)+([a-zA-Z0-9]{2,})+$/);
  if (goodEmail)
  {
    good = true;
  }
  else
  {
    alert('Please enter a valid address.');
    field.focus();
    field.select();
    good = false;
  }
}

u = window.location;

function mailThisUrl()
{
  good = false
  checkEmailAddress(document.eMailer.email);
  if (good)
  {
    window.location = "mailto:"+document.eMailer.email.value+"?subject="+initialsubj+"&body="+initialmsg
  }
}

</script>
<form name="eMailer">
Tell a friend:
<input type="text" name="email" size="26" value=" Enter Address Here" onFocus="this.value=''" onMouseOver="window.status='Enter email address here and tell a friend about this site...'; return true" onMouseOut="window.status='';return true">
<br>
<input type="button" value="Send this URL" onMouseOver="window.status='Click to send an email (with this page address) to a friend! Enter email address above...'; return true" onMouseOut="window.status='';return true" onClick="mailThisUrl();">
</form>