Rails Against The Machine

If you want local live search such as this example it turns out its pretty easy to do with jquery where as the prototype code is pretty horrific. Javascript is as follows

$(document).ready(function(){
 $('input#query_string').search();
});

$.fn.search = function() {

$(this).keyup(function(){
var searchString = $(this).val();
var searchElements = "#"+this.getAttribute("search_elements")+"> *";

   if (searchString.length > 1){
     $(searchElements).hide();
     $(searchElements+QueryString(searchString) ).show();
   }
   else {
   $(searchElements).show();
   }
 });
};

//Extend JQuery by defining Case insensitive search for containing text
jQuery.extend(jQuery.expr[':'], {
   Contains :
   "jQuery(a).text().toUpperCase().indexOf(m[3].toUpperCase())>=0"
 });

//Split the query string so that words separated by spaces
//then put this into a single query string
function QueryString(srch)
{
   srch=srch.split(/\s+/);
   query="";
   for (i in srch){
       query=query+':Contains(' +srch[i] + ')' ;
   }
   return query;
}

To use you need a text box such as

<%= text_field_tag :query_string , @query_string,{:search_elements=>'search_results'} %>

the items to filter on the basis of the query_string are all child divs of the div specified by 'search elements'

  <div id="search_results">
   <div>
     some item to filter
     <div>sub divs are also searched</div>
   </div>
   <div>
     some other item to filter
    </div>
 </div>