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)
Even if this is mostlikely impossible because when a typo isn't enough to redirect the transaction to another address but let's play the game.
If suddenly 100
BTC landed on my wallet I would re-send them to their owner (I can't sleep at night if I have funds that are not mine) and hopefully the owner will appreciate my act and will give me some tips
