yes you can have
some people sell these http://idsforsale.yolasite.com/
Yep, with different emails and usernames
If you use separate email addresses.
You can have as many as you want as long as you use a different email address.
sure, why not?
For example, well I don't know if you know RayWilliamJohnson , but he has at least 2 quite alot watched youtube accounts (i think the other one is breaking nyc or something)