N.B This is a lot of fun and a good way to understand how the Bitcoin network operates a little better!Whether it's an electronic wallet, a paper wallet or a brain wallet, you need to have both a public and private key. In simplest terms, your public key is a Bitcoin address where coins can be sent. Your private key is used to access the coins stored at that address.A brain wallet quite simply involves you memorising a private key so that only you can access your Bitcoins - in essence carrying your wallet in your head.This is so easy, it can be done in three steps.1. Firstly think of a memorable phrase or combination of words such as "I love Family Guy." What we'll do now is transform that phrase into a viable Private Key by using the cryptographic SHA256 function.If you have Linux, there's a command for this, example below:echo -n I love Family Guy | sha256sumIf you don't use Linux shame on you but there are a number of websites that can do this for you, try : http://hash.online-convert.com/sha256-generatorWhichever method you use you'll get a long string of meaningless numbers and letters, in this case:c3be1d4cf39643e384cda6074f8ff39aff7c725fe30fd5358abf7193af1d1d19Don't worry you don't have to memorise this!2. Use your Tor Browser to go www.bitaddress.org and click the tab labeled "Wallet Details." Disconnect from the internet then paste this long string into the box named "Enter Private Key (any format)". Click "View Details." The website will generate a BTC address at which you can receive funds.3. Send your Bitcoins to the Bitcoin address at the top of the page and congratulate yourself on having your own brain wallet!- How to check your balance:1. Repeat steps 1 & 2 above using the same words or phrase you used before to generate your private key.2. Highlight the Bitcoin address at the top of the page and copy it.3. Go to www.blockchain.info and paste the wallet address into the search bar at the top right. The website will show you the current balance.- How to get the Bitcoins out of your head! :-D1. Repeat steps 1 & 2 above using the same words or phrase you used before to generate your private key.2. Highlight and copy the row of numbers and letters on the page below where it says "Private Key WIF (51 characters base58, starts with a '5'):"3. In a new tab, go to www.blockchain.info and click create new wallet. 4. Click the "Wallet" tab, then click "Start a New Wallet". 5. Once you're logged in and have opened your wallet click the tab labeled "Import/Export". Click Continue.6. In the box underneath where it says "Import Private Key", paste the private key you copied earlier and click "Add Private Key."7. Your wallet will sync with the server. You can then click on the "Send Money" tab at the top to send the coins to another online wallet or a wallet on your computer.Have fun!V.