Wow, so many bugs today! First off, open http://play.clubpenguin.com/ in as many tabs as you want as long as it is two or more. Login to Club Penguin in each tab, one by one. Rather than the orange box saying you can only have one Club Penguin window open, you’ll be able to log in to unlimited penguins!
As you can see, I am on my main penguin, Trainman1405, as my friend’s penguin, Mandy26. Cool huh?