Last October a website called BTCBurns.cf identified 397 burn addresses containing 2,657.8686 BTC lost forever. It has gone offline. Since it stopped keeping track 26.04 additional bitcoins have been sent to these addresses.
The total number of unspendable bitcoins is now 2,771.4086.
http://bitcoinwhoswho.com/blog/2016/12/21/btc-burn-addresses/What is a burn adress?I`ve never heard about this.
How is it possible people to continue to send bitcoins to those adresses?
A burn address is an address that is created for people to send Bitcoins to them and make sure that it is unable to be used. The address does not have a private key that is known to anyone. An example of an address is this: 1CounterpartyXXXXXXXXXXXXXXXUWLpVr. It is extremely hard for anyone to generate an address that starts with 1CounterpartyXXXXXXXXXXXXXXX and thus the probability of it having a private key that is known to everyone is extremely low. Many motivations to doing this.
Some people just burn some of their Bitcoin to increase the value of it overall, and to be fair 2771BTC isn't a small amount and it is worth a huge amount.
As for everyone who thinks that the bitcoin really is lost forever, though, it's far from that. It'll take a long time to get to the address, but I would be willing to guarantee that someone will find it at some point. Assuming someone seriously undertakes that goal, though.
And when someone does it we should IMMEDIATELY switch to a different algorithm of generating wallet. Your "very long" is underestimating what power it is to crack an address. When you get that address, the earth probably wouldn't even exist.
lookup "proof of burn"
this is the only purposeful burning i am aware of
the rest of lost coins maybe someday retrievable when computers are powerful enough to break their passphrases
They aren't meant to be taken out. If anyone ever gets access to them, we should be fearing for our addresses to be cracked. This is impossible and if it does happen, we would have switched to a better algorithm to generating addresses.
Sending Bitcoins intentionally to an address that cannot be spent is irresponsible since it introduces blockchain spent as the UXTO of them will be stored forever. A better method would be to use OP_Return since they do not occupy any space in the node's UXTO.