I must say the sheer ambition of this project has me kind of stumped. Or the intense undergroundness about it. Or maybe the air of "hey, it can be done, and it's cool, so let's!" behind it. Plus, it's a very high profile example of the magics made possible by a common user script. Or a not so common user script, with some backend server support.
Picture the web. Yes, we are all familiar with it; it's mostly a content provider's world still. User scripts skewed this a bit in the direction of "a content provider's world, which geeks can remodel at will, sharing their site mods". Hoodwink brings it another large step towards a great big wiki, where any participant can scribble a comment somewhere for all to see, whether supported by the site host or not. How?
A hoodwinked browser adds comments and comment buttons to posts all over the web, layering another web on top of our familiar web. Not all web pages; only pages on web sites where a member of the community has tailored two parameters for what can be commented and where. The first is a regexp for URLs (to permalinks of commentable entities), the second an XPath selector (for picking out a spot in the web page where it would make sense to add a "comment this" button). Simple enough to work, obscure enough to look and feel like magic.
Comments are stored on a separate server hidden away behind additional layers of obscurity, where a common mortal does not risk to tread by mistake; conscious effort is required to find your way into the system, and chances of search engines scooping up content is even smaller. This is indeed an operation in the mists of shadows.
If you want to participate in the hooded fellowship, instructions are available. These are the prerequisites for teaching your browser the magic hand-shake to find any content on the hoodwink server, and once there, registered and let in among the druids, you find a customized user script that lets you see the hooded version of the web, and participate, both in scribbling, and, should you want to, becoming a druid yourself, adding site coverage following the hints and tips section.
Be aware, though, if you mind your privacy, that any step you take on the hooded web with the script turned on, will be shared with the hooded server, echoing back your complete click trail. It does not get exposed the way your Del.icio.us bookmarks show up for anyone to see, but your browsing history will leave your local computer, just as it does if you run the Google Toolbar and opt to show Page Rank, for instance (which also requires leaving a breadcrumb trail, to Google, wherever you stride across the web). Recent Greasemonkey versions make it very easy to turn scripts on and off with just a click on the Greasemonkey icon and checking or unchecking the script in the menu, on the other hand, so you can always switch back and forth between the underground enhanced and public web.
The good things do not end here, though. There is RSS too, and lots of it. This is in fact CommentBlogging in a fully developed form, where your commentary left on blogs and other pages anywhere are recorded and neatly packaged up in RSS feeds by author, by site and also in a joint feed of all recent comments, or winks, as they are called here. Very nicely executed indeed. A fourth feed is available on new sites spun into the network by the druidry too.
You can't read the feed in your web based feed readers, though. For technical reasons probably very intentionally designed that way, you need to use a feed reader running on your own machine, or build a proxy for echoing the feeds to where you want them. I believe these obscurity measures are a way of limiting explosive growth by holding back wide masses of common people, growing at a slow pace and attracting only a very geeky crowd of druids at the moment. I can see how that might be a rather good thing for a community like this.
Similar things have been done in the past, I believe by Alexa, using browser plugins, but I'm not sure what happened to them and if they are still operational today. Doing it more low profile like this might make it last longer, spreading more slowly. Not to mention giving the air of exclusivity that lies around the project like a thick white mist. There is very beautiful Magick going on when visiting the core server itself, too, where an AJAX based forum is woven out of thin air, the AJAX code itself not even present in the pages loaded from the server, as it all resides in the local user script. All the compositioning into actual HTML pages full of life and discussion is driven from your own browser, not as traditionally from a recipy fetched from the web server. The web turned backwards, or inside out, again.
I really like the contribution climate they have devised too; weave in ten previously not handled sites to become a druid, and have present druids confirm that the sites you weave indeed work. After that, I presume, you are versed enough with the regexps and XPath to take part in the elder druids' duties, similar to how wizards have ruled the MUDs throughout the ages.
How I stumbled on this secret shrine hidden in the depths of the darkest woods? I just retraced my steps to the Greaseblog, reading up on articles I had missed, and found a new nice Greasemonkey presentation from early December in a post where Aaron shares and shows off a new presentation engine of his.
Thanks, Chief Monkey and Googler. :-)