I'm interested in using EARL to aid me in deciding which links to visit, the idea being I can find out if someone has already evaluated a resource, then I can use this report to decide whether it's worthwhile visiting - e.g. if it's not WAI compliant in an area I know will prevent me accessing it I can just avoid.
To this end, I've started on an EARL client, this means I need a datastore aswell (I decided the Annotea support could be added later as there seems a general lack of interest, so I'm going to "KISS")
The datastore is a simple database which stores pairs of urls and their EARL report, nothing complicated, to access a report you simply construct a url http://jibbering.com/earl/query.asp?http://www.w3.org/ and the RDF EARL report is returned. To add an earl report you simply POST it to http://jibbering.com/earl/submit.asp
The EARL client, currently only exists for IE5 and later browsers, and adds another option to the contextmenu of the browser, "EARL" - this then queries the datastore and adds a CSS border to the links in the page depending on if the linked urls are in the datastore or not and whether they pass or failed the EARL report - currently this is very dumb client, simply looking at pass/fail regarding of what the test is, it's something to build on though.
The client is available from http://jibbering.com/earl/earlext.html to add it to the contextmenu, you need to edit your registry. This registry file will contains the changes needed. Then to execute the EARL client you use the "EARL" option in the contextmenu.
Technically the client is very simple, and implementing it for other browsers should not be a complicated job - using XUL in Mozilla should be trivial, and as soon as a Mozilla arrives which has XUL working out the box on my system I'll implement it, others are welcome to in the meantime, the http://jibbering.com/earl/ server should be reasonably stable, but no guarantees I'm afraid.
The EARL currently used is the same as the sample "template" EARL Sean Palmer recently published.with a few additions, a <moomin:hash> property, which is an MD5 hash of the documents content.
I've now filled my EARL database with a robot which looks just at ALT text on images, thus checking part of WCAG2.0 checkpoint 1.1, I've used http://jibbering.com/earl/WCAG2.0/1.1# to represent this - but would imagine this should be set over in the WAI W3 tree somewhere, this now gives a reasonable demonstration of what might be possible in the future, looking at part of the www.w3.org page for example, you get
Most important is more intelligent queries so that you can say which EARL reports you're interested in reading about - but we really need EARL reports before then in any case.
You could also Download Earl Client/Server/robot to install it locally.