<SELECT size=\\"1\\" name=\\"component\\">
<OPTION value=\\"\\">--Select Here--</OPTION>
<OPTION value=\\"1.3.6\\">1.3.6</OPTION>
<OPTION value=\\"1.3.5\\">1.3.5</OPTION>
<OPTION value=\\"others\\" onclick=\\"showOther();\\">others</OPTION>
</select>
function showOther(){
LayerAmount.innerHTML = \'<input type=text name=others>\';
}
<span id=\"LayerAmount\"> </span>
This should work, although its not tested. If it doesn\'t you should be able to work it out. If I\'ve missed something out got http://www.nationwide.co.uk , apply for a personal loan and this is on the second page after registration!
Hope this helps