Changing log4net configuration parameters at runtime

Since most of log4net configuration is specified in your application's configuration a question does come up on occasion how may I change this at runtime, depending on the user, etc.
Changing parameters at runtime for log4net is fairly simple - see the following code sample:

        /// 

        /// SMTP Appender custom configuration
        /// 
        public void InitializeLog4Net()
        {
            //We need access to the repositories for the loggers
            ILoggerRepository repository = LogManager.GetRepository();
            
            //Get only SmtpAppenders
            //can do it as such:
            //var appenders = repository.GetAppenders().Where(o => o is SmtpAppender).Select(o => (SmtpAppender)o);

            //Or a bit more readable
            var appenders= from o in repository.GetAppenders()
                      where o is SmtpAppender
                      select (SmtpAppender)o;

            foreach (SmtpAppender smtpAppender in appenders)
            {
                smtpAppender.To = "adam_tuliper@nowhere";
                //Make this config change active immediately
                smtpAppender.ActivateOptions();
            }
        }