This isn't a terrible idea, but I think it belongs in the header (maybe meta tags) of the page to be loaded. Then if you added a paywall to your site, you'd update your server config, rather than trying to round up every hyperlink to your site ever. Imagine if Chrome could do a HEAD one link deep, and indicate visually whether you'll actually be able to see the page, or whether you'll be solicited for some personal info.
In the meantime, someone could write a Chrome plugin that uses a blacklist to rewrite links to paywalled sites.
Yes, but they have no real incentive to put them there, since they want people to see the paywall (and possibly subscribe). Besides, many paywalls are dependent on the user (e.g. she may have some free views per month or so).
> I tend to recommend 1960s editions of Halliday and Resnick (not the recent ones!)
I'm curious why. I remember reading the second edition back in 1998. Recently, I got one of the new editions (8th) but the new ones seem too verbose. What went wrong?
In textbook publishing, it's very important to put out a new edition every year or two. Otherwise your sales will disappear, since everyone will buy the book used. For a book like Halliday and Resnick that's been around since the 1960s, it doesn't take a very large number of people selling theirs to satisfy the demand of all current physics students.
So you put out a new edition in which you shuffle all the exercises so that students can't do their homework, and you have someone mess with the text and the formatting to make it look like a real change. You add glossy pictures, because you get a much bigger visual impact from changing the pictures than from actually changing content.
For an old book, this is a problem because often the authors are dead or retired, or think the book is just fine. Now you have to find someone who would like his name added to a classic text who will sign off on the job. Today it's Halliday, Resnick, and Crane. For Arfken's old mathematical methods for physics text, it was Weber.
