It's not something you'd want to do as it's not a cool move at all and they most likely can detect multiple sign ups. I've actually signed up with 3 mails myself due to me panicking when I didn't receive the mail confirmation for the first 2 and when I asked if it was ok on their Twitter I got a generic "Please wait for the emails to come through, our servers are struggling". So, I don't think you'll get disqualified for it or anything (I certainly hope not) but I don't think it's a good move.
Also, remember that you're selected based on their needs so if you're in you're in regardless of how many applications you made.