<div id="one" name="some_div" onclick="meFirst(this);">
   Click me!
</div>
<div id="two" name="some_div" onclick="meFirst(this);">
   Click me!
</div>
<div id="three" name="some_div" onclick="meFirst(this);">
   Click me!
</div>
 

function meFirst(object) {
  activeDiv = object.id
  divGroup = object.getAttribute("name")
  allMyDivs = document.getElementsByName(divGroup);

  for(i=0; i < allMyDivs.length; i++ ) {
    var newContent = "";
    if( allMyDivs[i].id == activeDiv ) {
      newContent = "I rule!!";
    } else {
      newContent = "Click me next!!";
    }
    allMyDivs[i].innerHTML = newContent;
  }
}