On the PHP script (you knew I'd mention that again, right? ;) every article now has a link to its "printable version", currently without the logo and the links, just the article text, with a single line below it, stating the adress of both wikipedia and the article itself on the web. As people will prefer that version for printout (no links and other distracting stuff), the "paper linkback" should be solved by that.
IMHO, that linkback table is a little overkill for people who only want to use a single article (or just a part of it). Thinking about it, how about a little button to append at the end of the text (like the Nupedia "N") that links back to wikipedia.com or to the article itself? Linking to wikipedia.com might be better in the long run, because we can give a one-line-source for the button that needs no change; and, people who follow the link will see what we have to offer *in addition to* that specific article (which they can find using search pretty easy). Also, a small button wouldn't ruin layouts, is smaller than even a text link, but can still be quite visible (how about a white W on black background?)
Magnus