i am sorry, i would like to disagree.
it is forbidden to attempt to connect with the dead.
there are many references to this in the old testament, and in the new testament (luke 16:19-31) we have the story of lazarus and the rich man which clearly states that there is a 'great chasm' between the resting place of lazarus and the rich man in hades. lazarus is NOT permitted to go back to the earth to contact the rich man's relatives.
if anything supernatural happens in the ways we know it can from the Bible (forgiveness of sins, healing of the sick in the name of Jesus etc), then we can praise God for His mercy shown through His church.
but if anything supernatural happens which is not through the name of Jesus and through His church, then it must be through the evil spirits, or else it is just a trick or a joke.
there is ONLY ONE GOD, not many good spirits all competing for our attention. if something is not form God, it is either a joke (a waste of our time that we could spend in better ways), or, worse still, it is from the devil, who seeks to kill and destroy and confuse us and turn us from our faith.
the new testament letters are full of warnings against false teachings and idolatry. it is a very serious situation to be lead astray by false teachings and thrills and 'fun'.
i can't imagine any medium being in any orthodox church!
certainly in my church (coptic) and the eritrean church and in my friend's antiochian church, it is 'haram', forbidden, and a very serious sin.