Estou na Madeira e gostaria de comprar de alguem.

Pessoal, estou com um saldo no MP( do mercado livre ) alguém interessado em me vender Btcs ?

  I tried to use Brainwallet( https://brainwallet.github.io/#tx ) to send bitcoins
but i get a error message "bad request". I did fill every field correct...

Anyone have this same issue ?

Mining Bitcoin with pencil and paper


 I give up traditional ways....

 Mining Bitcoin with pencil and paper: 0.67 hashes per day
I decided to see how practical it would be to mine Bitcoin with pencil and paper. It turns out that the SHA-256 algorithm used for mining is pretty simple and can in fact be done by hand. Not surprisingly, the process is extremely slow compared to hardware mining and is entirely impractical. But performing the algorithm manually is a good way to understand exactly how it works.

A pencil-and-paper round of SHA-256
...
http://www.righto.com/2014/09/mining-bitcoin-with-pencil-and-paper.html

 It was never clear to me.
 After i sent some Btc, 'change' goes to a unknown address. How can i know previously this address ?
 
 How happens 'changes' process???