Humble bundle book bundles - download all books at once

hb_all_books_dl.js

/* 
After purchasing a humble book bundle, go to your download page for that bundle. 
Open a console window for the page and paste in the below javascript

this fork downloads all formats and does so without using jquery (since that didnt work for me)

note that if you are in chrome, chrome will not download the pdfs for you by default, to fix this
type “about:plugins” in the address bar and disable chrome's pdf viewer
*/
var pattern = /(MOBI|EPUB|PDF)$/i;
var nodes = document.getElementsByTagName('a');
for (i in nodes) {
    var a = nodes[i];
    if (a && a.text && pattern.test(a.text.trim())) {
        download(a.attributes['data-web'].value, i);
    }
}
function download(url, i) {
    var iframe = document.createElement('iframe');
    iframe.id = "dl_iframe_" + i;
    iframe.style.display = "none";
    document.getElementsByTagName('body')[0].appendChild(iframe);
    iframe.src = url;
    console.log('iframe set to', url)
}

Updated Pattern to get PDF (HQ), PDF (HD), CBZ files, and the Downloads of .zip's

var pattern = /(MOBI|EPUB|PDF( ?\(H.\))?|CBZ|Download)$/i;

For Chrome users:

The location of the plugins have changed, you can set the required field here:
Settings (chrome://settings) --> Advanced --> Privacy and security --> Content settings --> PDF documents --> Download PDF files instead of automatically opening them in Chrome --> Turn ON

Moreover, I recommend turning off for asking download location:
Settings (chrome://settings) --> Advanced --> Downloads --> Ask where to save each file before downloading --> Turn OFF

Doesn't like: download(a.attributes['data-web'].value, i);

Uncaught TypeError: Cannot read property 'value' of undefined at <anonymous>:6:42

On my Firefox I got an error: TypeError: a.attributes['data-web'] is undefined
So I changed the line 15:

download(a.attributes['data-web'].value, i);

To:

download(a.attributes['href'].value, i);