Computing ANYTIME!

Working with DateTime and the DB can be tricky in C#.  The easiest way to insert a DateTime robustly in to the DB is to use a prepared statement

cmd.Parameters.AddWithValue("@Date", DateTime.Now);

2) Inserting a Null Value into the Db

As a second point it, I had a situation where it was important to work with a nullable date time in the DB, in this case DBNull.Value should be used as follows:

cmd.Parameters.AddWithValue("@Date", DBNull.Value);