Bitcoin Forum

Brain Wallet Challenges - Challenges provide a Bitcoin Bounty held in a Wallet secured by a Guessable Passphrase.

Description:

Challenges provide a Bitcoin Bounty held in a Wallet secured by a Guessable Passphrase. Each challenge has a set category and a set number of hints. Hints must be purchased, but a portion of all hint fees are added to the Bounty!

Links:

Brain Wallet Challenge (www.reddit.com/r/brainwalletchallenge) (http://www.reddit.com/r/brainwalletchallenge)
Welcome Post (http://www.reddit.com/r/brainwalletchallenge/comments/28hbej/welcome_to_brain_wallet_challenge/)
Challenge #1:  Movie Quote (http://www.reddit.com/r/brainwalletchallenge/comments/28hdm8/challenge_1_movie_quote/)

Frequently Asked Questions:

• What's a Brain Wallet? - A brainwallet refers to the concept of storing Bitcoins in one's own mind by memorization of a passphrase.
• Is there a site I can use to generate the Brain Wallets? - Absolutely, check out brainwallet.org
• When are new challenges posted? - After the current challenge is beaten. All new challenges will be flared as such.
• How much does a Hint cost? - The formula is (Total Bounty / Total Hints) * 1.5
• How much of the hint price is added to the Bounty? - 15% goes into the bounty of the current challenge.
• What happens to the rest? - 85% goes towards recouping funds for the next challenge, as well as operational costs.
• How do the hints work? - Each challenge has a set number of hints. The hints get much more specific as you purchase more. Buying all the hints or even most of them essentially gives you the answer. However, be resourceful and you will solve the challenge far before then. Remember that a portion of every hint payment goes towards the bounty. More players equals a higher bounty!
• What is a Salt and how do I use it? - The salt is a random, 10-character string added to the beginning of the challenge passphrase. This will be given to you in the initial post.

Getting Started:

You'll need a Reddit account (as the games are hosted on Reddit) and a ChangeTip account (more information on changetip can be found on their subreddit /r/changetip (http://www.reddit.com/r/changetip) or their website www.changetip.com (http://www.changetip.com)).  Subscribe to the /r/brainwalletchallenge (http://www.reddit.com/r/brainwalletchallenge) subreddit to stay informed of new challenges.  Purchased hints will be sent to you via a private message on Reddit.

Example Profit Chart (Challenge #1):

The following is the profit table, the column title indicates the number of assumed players; as more contestants buy hints, the profits will increase.  Remember 0.001125 BTC is being added to the bounty for each hint purchased.

Hint	1 Player	2 Players	3 Players	4 Players	5 Players
1	0.093625	0.09475	0.095875	0.097	0.098125
2	0.08725	0.0895	0.09175	0.094	0.09625
3	0.080875	0.08425	0.087625	0.091	0.094375
4	0.0745	0.079	0.0835	0.088	0.0925
5	0.068125	0.07375	0.079375	0.085	0.090625
6	0.06175	0.0685	0.07525	0.082	0.08875
7	0.055375	0.06325	0.071125	0.079	0.086875
8	0.049	0.058	0.067	0.076	0.085
9	0.042625	0.05275	0.062875	0.073	0.083125
10	0.03625	0.0475	0.05875	0.07	0.08125
11	0.029875	0.04225	0.054625	0.067	0.079375
12	0.0235	0.037	0.0505	0.064	0.0775
13	0.017125	0.03175	0.046375	0.061	0.075625
14	0.01075	0.0265	0.04225	0.058	0.07375
15	0.004375	0.02125	0.038125	0.055	0.071875
16	-0.002	0.016	0.034	0.052	0.07
17	-0.008375	0.01075	0.029875	0.049	0.068125
18	-0.01475	0.0055	0.02575	0.046	0.06625
19	-0.021125	0.00025	0.021625	0.043	0.064375
20	-0.0275	-0.005	0.0175	0.04	0.0625

One thing we are likely to do is post a second challenge tonight, which has a smaller bounty, and therefore, smaller hint prices. This will hopefully let people try the game out, with a much smaller investment.

Will the answers be all lowercase, no punctuation or numbers, and will the words have spaces between them? And will the keys be compressed or uncompressed?

That it was a movie quote was enough of a hint for me  ;)

https://blockchain.info/tx/dc5c482786e802511b06c1f6b0e40fdc9ccb54ad8a00273d17a72aed638f45cd

The brainwallet phrase was "7nkegz38aY Richard, this is just the kind of pretentious bullshit that Americans always say to French girls so they can sleep with them."

It's from The Beach: https://en.wikiquote.org/wiki/The_Beach_%28film%29

lol well done, although now I assume you have a brain wallet cracking rig ready to accept new dictionaries whenever.

i downloaded a python script i found via a google search and then downloaded the wikiquote xml dump, filtered out any non-film records, split the records into individual quotes and then run it through the python cracker. the last step was the slowest step. i'm surprised somebody with a gpu cracker didn't gobble this up immediately.

Well at least you got it in early days, before people had wasted too much money on it.

One of Leo's less known, but nonetheless very good works.

I'm hoping you will post in the Reddit thread, so that you can be given proper credit and the user flair!

And of course I hope you'll play in future ones, where I come up with clever ways to ensure your process doesn't work so easily muhahaha.

Challenge #2 is now up.  Good Luck!

Quick update. Challenge #2 remains unsolved. However, the bounty is now up to 0.0154 BTC. Hints 1-5 are unlocked as of this morning.

Challenge #2 (http://www.reddit.com/r/brainwalletchallenge/comments/28mca2/challenge_2_culture/) is STILL UNSOLVED!

The bounty is sitting at a balance of 0.0193 BTC (1EDfjQ6NSYfAKSgv2VxwQ1bw3iKQ5w7Erj (https://blockchain.info/address/1EDfjQ6NSYfAKSgv2VxwQ1bw3iKQ5w7Erj)).

Hints 1 - 10 are unlocked, and each hint only costs 0.001 BTC - in addition, if you buy the first THREE hints, we'll give you the fourth FREE.

Hope to see you playing soon.

Good luck!

If you give a free tip maybe get people a bit interested? Seems a bit stagnate at the moment.

Agreed!  We're actually about to release an entirely FREE challenge, just as a promotion.

We are offering a deal, buy three, get the fourth free!