JsonNetResult for ASP.NET MVC - correct formatting of dates and camel cased properties Got most of the code from Stack Overflow.

JsonNetResult

    using System;
    using System.Web;
    using System.Web.Mvc;
    using Newtonsoft.Json;
    using Newtonsoft.Json.Serialization;

    public class JsonNetResult : JsonResult
    {
        public override void ExecuteResult(ControllerContext context)
        {
            if (context == null)
            {
                throw new ArgumentNullException("context");
            }

            var response = context.HttpContext.Response;

            response.ContentType = !string.IsNullOrEmpty(this.ContentType) ? this.ContentType : "application/json";

            if (this.ContentEncoding != null)
            {
                response.ContentEncoding = this.ContentEncoding;
            }

            if (this.Data == null)
            {
                return;
            }

            var jsonSerializerSettings = new JsonSerializerSettings();
            jsonSerializerSettings.DateFormatHandling = DateFormatHandling.IsoDateFormat;
            jsonSerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
            var formatting = HttpContext.Current != null && HttpContext.Current.IsDebuggingEnabled ? Formatting.Indented : Formatting.None;
            var serializedObject = JsonConvert.SerializeObject(Data, formatting, jsonSerializerSettings);
            response.Write(serializedObject);
        }
    }

How would one use this inside of an action?

Ricky Wan shows how to incorporate JsonNetResult into your code by overriding the Controller.Json method
http://wingkaiwan.com/2012/12/28/replacing-mvc-javascriptserializer-with-json-net-jsonserializer/