Generate a Unix Timestamp in C#

This code will allow you to generate a unix timestamp for a given DateTime, turn a unix timestamp back into a DateTime, or get the current unix timestamp.

64-bit version (future proof)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace XeonProductions
{
    static class UnixTimestamp
    {
        public static DateTime UnixEpoch = new DateTime(1970, 1, 1, 0, 0, 0, 0);

        public static ulong DateTimeToUnixTimestamp(DateTime time)
        {
            return (ulong)(time - UnixEpoch).TotalSeconds;
        }

        public static DateTime UnixTimestampToDateTime(ulong timestamp)
        {
            return UnixEpoch.AddSeconds(timestamp);
        }

        public static ulong Now
        {
            get
            {
                return (ulong)(DateTime.UtcNow - UnixEpoch).TotalSeconds;
            }
        }
    }
}

32-bit signed version

using System;
using