There is a bug when you display a DateTime property, and one of the documents doesn't have that property filled out:

2014-03-04 10:28:17,661 [24] ERROR Umbraco.Core.UmbracoApplicationBase - [Thread 24] An unhandled exception occurred
System.FormatException: String was not recognized as a valid DateTime.
   at System.DateTime.Parse(String s)
   at System.Linq.EnumerableSorter`2.ComputeKeys(TElement[] elements, Int32 count)
   at System.Linq.EnumerableSorter`1.Sort(TElement[] elements, Int32 count)
   at System.Linq.OrderedEnumerable`1.<GetEnumerator>d__0.MoveNext()
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at uChildListDataType.TableData.ProcessRequest(HttpContext context)
   at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)