LINQ-to-MongoDB.cs

public Post GetMostRecentPost()
{
  Post mostRecentPost;

  using(var db = Mongo.Create("mongodb://localhost/BlogApp"))
  {
     var posts = db.GetCollection<Post>();
     //create a LINQ queryable to search the DB.
     var q = posts.AsQueryable();

     //the ordering happens on the server and only one result will be returned.
     mostRecentPost = q.OrderByDescending(y=>y.PostDate).FirstOrDefault();
  }

  return mostRecentPost;
}