I think this is a pretty good idea - you might also want to take a look at: https://ubtcbank.com/

(it is using the same sort of approach technically)

best bet is to not use third party services that offer you private keys..

although i have not heard anything bad about bitaddress.org or the other suggestions above. safest bet is to clean wiperecover your computer to factory settings. use ur own client EG bitcoin D to give u a fresh address and privkey.. then write it down on a piece of paper laminate it and put it in a safety deposit box.

making websites that ask you to type in their priv keys, will make a few people think.. hmmm why would they ask.

if anyone truly wanted to split their priv key up.. think of the easy way...

1 x paper 1 x scissors = 2x paper

store each piece in separate places

simply store the key without a note what it is.

So you'd like to have a secure paper wallet for dummies? But you want to avoid the trouble of making sure you have access to an uncompromised system? Why doesn't that make sense to me?

True - the technical stuff would need to be hidden "under the hood" with your idea but what they are doing is creating "two signature" keys (which I believe is the main thing necessary for security).

I appreciate the effort to establish a protocol for creating a secure paper wallet which even works if the used systems are compromised. Know that the user needs to use two uncorrelated systems though, because if both systems are compromised, chances are they are compromised by the same entity. I propose using a home computer and then maybe go to an apple retail store or best buys and create another component there...

If I understand correctly, you will have 2 private keys (5J... and 5H... for example) combined to make a 3rd private key (5K...).

Could you send 0.10 BTC to the first address (5J...) and 0.10 to the 2nd (5H...) but send 100 btc to the 3rd (5K...)

Set up to be notified when one of the first 2 addresses are drained, this lets you know you have been compromised on 1 system.

compromised system??

lol maybe next time u should include the first part of my quote.. restore/recover system to factory settings.

but if u easily get a compromised system then ofcourse ur also gonna be deluded to trust typing your private key into some script kiddies website so they can do magical things to your private key.

simple fact about paper wallet is.. keep it on paper dont give it out to third party websites. and dont obtain it from third party websites either.

a paper wallet is just that. a paper wallet. anyone saying they are solving paper security by designing a website. has no idea what paper wallets are all about.

make it from ur own CLEAN system print it out and the only thing u have to worry about is someone in your real world life reading it. so cutting it in half and putting it in 2 locations will reduce that from happening.

I don't understand what you are asking:  if your system holding your wallet is compromised already, your wallet is toast.  Get a system that will never touch the internet again, wipe it and put a clean version of whatever OS you want on it.  Install Bitcoin software (insert Armory plug here), and manually copy down the private keys and addresses (in Armory, it is "Backup Individual Keys").  There's your paper wallet.  If you want to "watch" it, produce a watching-only wallet.

In the absence of any good multi-sig solutions, you can do "manual" multi-sig using Armory's built-in ECDSA calculator.  It requires some mathematical prowess, but everything you need to know is on the forums.  The gist is:  create two private keys on two separate computers that have never touched the internet.  Copy/print the private keys on separate pieces of paper and store them away safely.  Copy/print the public keys and exchange them.  Now one computer has PrivA & PubB, and the other one has PubA & PrivB.   Both systems can use this to create a public key that is associated with a private key that is only recoverable when both original private keys are on the same computer. 

You can use this address for collecting money.  Use it for savings.  But it will be a bitch to move:  you'll have to transfer the private key from one computer to another.  Then plug them into the ECDSA calculator to get the master private key.  Create a new wallet and import that private key.  Then sign the transaction and take to an online computer to broadcast.

I don't actually recommend this because it's not simple by any means, but if you are that hardcore it can be done.  That's actually why I made the ECDSA calculator, for devs, and hardcore users like (and for myself to check ECDSA math when debugging stuff).  But it sounds like you're looking for something like this.

No, you don't understand. If I did anything at all it would be exactly like bitaddress,org where the html file can be saved and used offline any time, and completely open source and verifiable by anyone.

The point is that each private key generated would only exist and be printed from one system.

But one key is not enough to actually spend coins.

So a hacker would have to compromise two distinct and preferably unrelated systems in order to obtain a working spendable key.

The only thing someone uploads to the second system is the public key from the first system. The public also does not allow spending coins in any way.

The only reason to have it as a web site is to make it easy to distribute and use (it can have help text saying what to do) but it need not be online and connected when generating a key, in the same way that bitaddress.org doesn't need to be.