"Siddhis are spiritual, magical, supranatural powers acquired through sadhana(spiritual practices), such as meditation and yoga.
People who have attained this state are formally known as siddhas.
In Hinduism eight siddhis(Ashta Siddhi) are known: expanding one's body to an infinitely large size, Garima: becoming infinitely heavy, Laghima: becoming almost weightless, Prapti: having unrestricted access to all places, Prakamya: realizing whatever one desires, Istva: possessing absolute lordship, and Vastva: the power to subjugate all."
I think many of the devotees of Maharajji's satsang have developed secret siddhis. They will never admit to that, ever, for then these powers are lost. Nevertheless, the siddhis are there.