Well, most wallet programs choose which output(s) to spend on your behalf. You can, however, make a raw transaction, and choose which of the outputs to spend, and where they go. You can even choose to send bitcoins to
nowhere - effectively destroying them.
However, after doing some research about raw transactions, you CAN decide which outputs you want to spend and which you want to keep in the address.
As long as outputs are spent one at a time, they aren't mixed at all. They just stay in the same spot for a little while.
Not many people use raw transactions (because not many people move coins around for their numismatic value!) but you can learn how it's done with a few google searches.
I've definitely learned something new. Which I may find useful in fact, for a project or two I've been kicking around in my head. Many thanks and my hats off to you Mr Taras
(and Mr Notme, who pointed out my error as well!)
Here is a source I found useful and appropriate to my current level of understanding:
https://en.bitcoin.it/wiki/TransactionsYou can even choose to send bitcoins to nowhere - effectively destroying them.
Didn't Karpeles do that at one point? Or was that an unsubstantiated rumor?
I use them for redeeming paper wallets on an offline computer without ever letting the private key touch a computer that has ever been on the internet.
I use Armory for that. But perhaps I will learn how to make paper wallets and redeem them without Armory. Will be fun to dig around under the bitcoin hood and see what I can do.
Oh, and dooglus let me submit two raw transactions for 1,000 BTC each (for just-dice)! That was awesome!
Enough to buy a slice of pizza at one point in history. Or a small army in the not too distant future ...
The coolest technical thing I've done with crypto is to code a website to take payment in bitcoin for subscriptions to the site, using a deterministic Master Public Key to generate a unique receipt address for each subscription. Private keys are not stored online so I don't have to worry about hackers stealing the bitcoin.