The 2006 issue of the award winning (thanks to PDFfolio) IRS Tax Products CD-ROM is now out. It can be ordered from NITS, and is shipped worldwide.
As in the earlier versions, the navigation and product finding system is using PDFfolio, as it has been reported in this case study.
The 2006 issue comes with an additional goodie, showing the scalability of PDFfolio. The package contains also the IRS Tax Products Historical DVD, which essentially which essentially has all the tax forms published by the IRS since 1913, and all IRS publications since 1994. This translates to more than 3000 products with built in links to up to 93 different versions for a single product. And all that information fits into a PDF file of roughly 900 kB in size (the CD with the current products contains 1390 products and the main PDF file is 540 kB in size). The access to all versions of a product on the DVD is provided via a hierarchical popup menu, as it is shown in this screenshot:
Hierarchical selection popup menu: A hierarchical popup menu to select a version of a product in the IRS Tax Products Historical DVD.