One of the fundamental tennents of Ted Nelson's Xanadu is transclusion; the World Wide Web as we know it has a very limited version of that and it's mostly limited to images. It's pretty easy to do in HTML:
<IMG SRC="http://grumpy.conman.org/2003/06/01/new-laptop.jpg" WIDTH="190" HEIGHT="241" ALT="[Picture of Mark's new laptop]" TITLE="Picture of Mark's new laptop">
Instant transclusion of an image.
And there have been plenty of times I would have liked the ability to transclude portions of HTML as well (technically, you can do whole HTML pages—Spring is doing that for her Live Journal friends page on her own journal—doing portions is a bit harder) since that would make it easier to quote the page I might link to (as I did on Baby names gone bad).
But there are two problems with transclusion. The first problem is the dead page problem. Web pages go dead with alarming regularity (in fact, check out my first post and follow the link—it's no longer there) and thus the page you might have once transcluded is no longer the page you think is being transcluded. Ted Nelson avoided this problem by stipulating that once a page was created, it exists until the end of time. Highly optimistic outlook on his part (and there are instances where people might not want a page to exist until the end of time).
The second problem is one I'm now struggling with: do I want my stuff transcluded? Especially if I'm footing the bandwidth bill?
Over the past few months I've noticed that several of the pictures I've put up here in the Boston Diaries are being referenced from other pages, just like I've included Mark's picture on this entry. And I'm not sure how I feel about that. On the one hand, the amount of bandwidth incurred isn't that much, considering how much bandwidth overall this server is pumping out each month. But on the other hand, it still is my bandwidth and the images are being displayed in a context I might not want.
Oh yes, I've tried looking at the pages that include my images. And while some of the pages I can see how the image is used in the new context (and universally the pages including my images are web based message boards), about half the pages are locked from my view since I'm not a member of that particular message board.
A few months ago I wrote one the webmaster of one of the message boards about my image being used (I was just curious to see the page it was on) and it was taken care of (the webmaster removed the link to my image). But this is going on more and more, and I'm not quite sure how to address this; or even if it's a real problem I should be worried about.
I was talking to Mark about this tonight and he was of the opinion that this was wrong and that it would be an easy fix to check the referring link and refuse to serve up the picture, or serve up an alternative picture:
Although there are cases when I might want to include the image on another webpage elsewhere, so I have to have some way of indicating if an images can be transcluded or not, or have a way of specifying which pages are allowed to include this image (or anything else that can currently be transcluded). Ted Nelson's overly optimistic solution to this problem (well, the bandwidth problem, not necessarily the permissions problem) was one of royalty payments, aka micropayments. But even if we had a workable micropayment system, other problems, like the “pay-as-you-play” problem (everything else being equal, people like flat rates).