How many lost bitcoins are there?

[Prolifik]

How many bitcoins do you think are out there that will never be used. Because they have been lost or forgotten.

I'm guessing at least a hundred thousand, but it could be over a million. Is there a way to use the blockchain to see bitcoins that haven't moved in x number of years. It would be an interesting statistic.

[wopwop]

about 20 million

[Prolifik]

There isn't even 20 million coins out there to be lost.
There might be 20 million lost wallets. Definitely not 20 million lost Bitcoins.

[CEG5952]

satoshi is a big question mark -- lots of coins there

i imagine there is millions -- how many, hard to know -- aside from that. i lost a couple dozen coins from 2010 personally.

[nahtnam]

I would say about 3 million will never be used or heard of again...

EDIT: Maybe 5...