Here is some expensive proprietary software that does the same thing, but is faster and many times more powerful. It has a free thirty day trial, and you can download tons of images in thirty days. Illegal full copies are also available if you are a pirate.
Offline Explorer Enterprise:
http://www.metaproducts.com/mp/Offline_Explorer_Enterprise.htmHere is comparable software without a thirty-day trial, also available free for pirates.
Teleport Ultra:
http://www.tenmax.com/teleport/ultra/home.htmIf you use an offline browser/website downloading tool, please use it responsibly. Each program has safeguards to avoid overloading servers. I cannot stress this enough: it is very important that you use these. Please read the directions and set your program settings and options carefully.
Here is a search engine to find Japanese fan search engines:
http://cluster.x0.to/search/top.htmlHere is a Firefox extension that copies all URLs of open tabs to the clipboard so that you can feed long lists of web addresses to your offline browser.
Tab URL Copier:
https://addons.mozilla.org/en-US/firefox/addon/2069Here's a web translation firefox extension that I haven't personally tried, but will probably be useful if you're not used to navigating Japanese websites:
https://addons.mozilla.org/en-US/firefox/addon/2444