[TadW]

It's fine if you are willing to give up some of your privacy. The small print:

When you use Adobe software to open a PDF file that contains sponsor content, your computer will connect to a website operated by Adobe, an advertiser, or other third party. Your Internet protocol (IP) address is sent when your computer accesses any website. The party hosting the website may use technology to send (or "serve") advertising or other electronic content that appears in a rendered file. That party may also use JavaScript, web beacons (also known as action tags or single-pixel gifs), and other technologies to increase and measure the effectiveness of its business and advertisements, and to personalize advertising content. Your use of, and communication with, Adobe websites is governed by the Adobe Online Privacy Policy found at http://www.adobe.com/misc/privacy.html. Adobe may not have access to or control over features that a third party may use, and the information practices of third party websites are not covered by the Adobe Online Privacy Policy.