i am just collecting info about lost bitcoins.
i want addresses with lost private keys / no private keys / or any other addresses with unavailable bitcoins
is anybody can point me if such data set is already exist or just post such addresses here.
There is nothing you can do about lost bitcoins and I dont think there is anything you can do about them. There is no services or such that tracks lost bitcoins and you cant know its lost until the owner of the address admits that it is lost and they no longer have access to it, and even after that, there is no way to recover those lost bitcoins as long as the owner cannot remember the key they used to lock it.
there has been a lot of loss of bitcoin but it can't be found anymore because every day the transaction is so many that it makes it difficult for us to track
The funniest thing is that there is no way to tell if the Bitcoin in an address is lost or being saved for a rainy day. The only way you can know they are lost is that the users comes open about it. Just like that of James Howells of Wales that lost about 7,500 bitcoins (damn!)and there was no way for him to recover it. That would he worth a lot of money by now. I also see a lot of people at the services section of the forum that post their addresses with lost bitcoins in it and there havent been any success in recovering those coins till date.