I keep writing this code - now I can find it on my blog in the future :-)

public static class StringXmlSerializer

{

   public static string Serialize<T>(T obj)

   {

      XmlSerializer s = new XmlSerializer(typeof(T));

      StringBuilder sb = new StringBuilder();

      StringWriter sw = new StringWriter(sb);

      s.Serialize(sw, obj);

      return sb.ToString();

   }

   public static T Deserialize<T>(string str)

   {

      XmlSerializer s = new XmlSerializer(typeof(T));

      StringReader sr = new StringReader(str);

      return (T)s.Deserialize(sr);

   }

}