In the Qur'an it says that you can hide your faith if you fear for your life.
If you are referring to 16:106, then that is only a shia interpetration and that too restricted at fear of death. Not as a means to form a hidden society and take over the world like some elders of zion conspiracy where Obama being a secret Muslim is brought up.
Close to 90% of the Muslims are sunni where this is not acceptable theologically. This doesn't mean ofcourse that some muslims might have done so for example under the Spanish inquisisitions when large scale Muslim and Jewish killings were perpetrated by the Conquistadar forces
Are Muslims allowed to hide their faith? - Slate Magazine