We have all read stories of coins being sent to wrong addresses (typos or badly copy and pastes)
What would you do if 100 Btc landed into your account? (unfortunately this has not happened to me yet)
Will thank you if this will happen to me. 100 bitcoins could make me a millionaire. Unfortunately there no way that you can retrieve your bitcoins sent to a wrong address unless he/she sent it to you back. That is my understanding.