Everyone knows gmail is invite only. In order to get a gmail invite you need to send an invitation to a non gmail address and then sign up. Well you could use your hotmail, yahoo, and other email addresses to get multiple accounts, or just send the invites to address that dont exist and the bounce backs will contain the link to sign up new accounts which you can just click on and register with from the bounce back error message. Simple and stupid but easier than signing up for accounts on other free services to get more gmail accounts.