JSONQuery provides a comprehensive set of data querying tools including 
filtering, recursive search, sorting, mapping, range selection, and flexible 
expressions with wildcard string comparisons and various operators.

Quick Examples:
    var data = {customers:[
      {name:"Susan", purchases:29},
      {name:"Kim", purchases:150}, 
      {name:"Jake", purchases:27}
    ]};
    
    var results = JSONQuery("$.customers[?purchases > 21 & name='Jake'][\\purchases]",data);
    results 
    
    returns customers sorted by higest number of purchases to lowest.
    
    
For more advanced querying capabilities, see:
http://www.sitepen.com/blog/2008/09/23/effortless-offline-with-offlinerest/