Yes you can. Tropicana Online Casino and Virgin Casino are both backed by the same parent company, GameSys, and are largely identical to one another. Both of them carry most of the same games, and offer the same exact welcome bonus for new players. That means you can head over to Tropicana and grab the bonus there, then create an account on Virgin and cash in the same bonus a second time. Of course, you should not create more than one account per site. If you do, you will be in violation of the the terms and conditions and have your account shut down.