gistfile1.js

function encryptROT13 (message) {
    var input = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz',
        output = 'NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm',
        rtn = [],
        i
    ;

    for (i in message) {
        rtn[i] = output[input.indexOf(message[i])] || message[i];
    }

    return rtn.join('');
}

function decryptROT13 (message) {
    var output = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz',
        input = 'NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm',
        rtn = [],
        i
    ;

    for (i in message) {
        rtn[i] = output[input.indexOf(message[i])] || message[i];
    }

    return rtn.join('');
}

function stringToBinaryWords (message) {
    var r = [],
        i
    ;

    for(i in message) {
        var current = message.charCodeAt(i).toString(2);
        current = "00000000".substr(current.length) + current;
        r.push(current)
    }

    return r.join(' ');
}

function binaryWordsToString (message) {
    var r = "",
        i
    ;

    message = message.split(" ");

    for (i in message) {
        r += String.fromCharCode(parseInt(message[i],2));
    };

    return r;
}


function reverseBinary (message) {
    var i,
        rtn = [],
        lookup = {
          '0': '1',
          '1': '0',
          ' ': ' '
        }
    ;

    for (i in message) {
        rtn.push(lookup[message[i]]);
    }

    return rtn.join('');
}

function encrypt (message) {
    message = encryptROT13(message);
    message = stringToBinaryWords(message);
    message = reverseBinary(message);

    return message;
}

function decrypt (message) {
    message = reverseBinary(message);
    message = binaryWordsToString(message);
    message = decryptROT13(message);

    return message;
}