Noda Time: An Advanced Date/Time Library for .NET

To put it bluntly, the date/time libraries in .NET are flawed. From the beginning there were no concepts of time zones or really any sort of universal time. As a result most libraries were designed to accept a DateTime class and left the developer to guess if the value should be in local or UTC time. For client server applications the problem was even worse, as local could mean client local or server local time.

via InfoQ: Noda Time: An Advanced Date/Time Library for .NET.