Change email configuration on the fly.
use \Swift_Mailer;
use \Swift_SmtpTransport as SmtpTransport;
// Setup a new SmtpTransport instance for Gmail
$transport = SmtpTransport::newInstance('smtp.gmail.com', 465, 'ssl');
$transport->setUsername('you@gmail.com');
$transport->setPassword('yourpassword123');
// Assign a new SmtpTransport to SwiftMailer
$gmail = new Swift_Mailer($transport);
// Assign it to the Laravel Mailer
Mail::setSwiftMailer($gmail);
// Send your message
Mail::send();