Computer Hacking (security): At what point in the future will it be possible to bruteforce a 20 character password consisting of upper case letters, lower case letters and numbers?

You may or may not be aware of this service: http://www.walletrecoveryservices.com/ Unfortunately, it doesn't look like good news. If you know some of the password this can help shortcut the decryption process otherwise it will take too long. From the site: If you have no idea at all of your passphrase, and it was more than a handful of characters long, then we cannot help you. No-one in the world, including the NSA, CIA, D-Wave or anyone else can crack the encryption used in the bitcoin wallet if the passphrase is more than 15 fairly random characters. The bitcoin wallet encryption is strong by design. There are no known flaws in the implementation, and many people have tried to break it! Here is some more bad news: http://security.stackexchange.com/questions/9427/what-are-the-odds-of-brute-forcing-an-archive-with-256-bit-encryption From the article: If you used upper/lower-case, numbers and non-alpha lets assume there are 70 possible characters used in the password. The password then has 70^20 possible permutations which is about 8e36. Assuming your rig could churn ten billion permutations per second (which is way, way more than you could do on an i5) the time to exhaust the complete set of permutations would be 2.5e19 years - which is about 5 billion times longer than the time until the sun consumes our solar system. Note: The above assumes you have a means of testing 10,000,000,000 permutations per second. Apparently Bitcoin uses a technique known as "key hardening" so you'll be lucky to get 10 permutations per second. This gives an estimation of decryption time using todays technology of around 2.5e28 years. So, how long before Moores Law reduces this to a reasonable time frame like 1 year? Answer: 141.5 years ... For the avoidance of doubt. Do NOT give up and delete your wallet. Who knows what might happen. A flaw may be discovered in the Bitcoin wallet encryption. A super powerful (and cheap) quantum computer may be developed. Bitcoin may become worthless. Or maybe you just end up passing on a fortune to your great, great, great, great, great, great, grandchildren ... ? For anyone interested, I used this http://www.calculator.net/half-life-calculator.html?type=1&nt=1&n0=25000000000000000000000000000&t=&t12=1.5&x=47&y=12 to get the value of 141.5 years assuming processing power doubles every 18 months.