Patrick H. Lauke (recenter) made a "GeoURL backwards" Firefox extension. If you install it, it'll light up a little GeoURL globe when the page you are on has ICBM headers. If you click the globe you get sent to see a list of sites nearby. It's really clever.
You can install it by clicking here: http://www.splintered.co.uk/extensions/geourl_0.2.xpi
update - It's now listed on addons.mozilla.org
update - someone else made another 1.5 extension.
Firefox will show a warning at the top of the screen, to proceed click "Edit options" and then "Allow" in the dialog that comes up. That'll make Firefox trust Patrick's site. Click "OK" and then click on the link to the extension again. When the extension has been installed you have to restart Firefox and then get the extension active in the toolbar by going to the menu "View" - "Toolbars" - "Customize" and then drag the GeoURL icon up to the toolbar. Whee, that was a lot of work. But try it, you'll like it.
update - Mark Zeman made a flickr world map extension based on the GeoURL extension.
additionally, with version 0.2, you don't have to explicitly add the button to the toolbar, as the extension automatically adds a small GeoURL indicator/button in the browser's status bar. of course, both status bar button and toolbar button can be used simultaneously.
I mention another GeoTag FireFox extension in my blog at http://home.alltel.net/jackwolfgang/blog/2005/02/geotags-firefox-extension.html. The actual extension is not my work, but did live at http://www.highearthorbit.com.
Excellent indeed. Just installed it :) Well done Patrick.
Here's a bonus-round suggestion: is there anyway to figure out the current center-point of a google-maps page and activate the extension? That would be cool. I guess it would be cooler to just get Google to integrate the standard meta tag into the results page. That would take someone all of five minutes. Maybe fifteen if they also updated the values of the meta-tag when you dragged the map.
Actually, also cool would be a way to plug in more destinations, as in the search-box in the firefox menubar. Can you make something in the status bar pop-up a menu?
Any chance of a Mozilla extension?
It would be really great if this extension were compatible with Mozilla.
I tried installing it, and it actually installs without any error message, but on restarting the browser the status bar turns into (part of) an error message - it looks like it's pointing to a tag it doesn't understand - but the actual message text is missing.
So I'm afraid I had to uninstall it again...
(I don't use Firefox since it doesn't support link element navigation (HTML 2.0!) which Mozilla does nicely and which I use a lot.)
New version of the FF extension is out, which combines the functionality of the flickr world map extension and the geotag extension. New to this version is a context menu on the statusbar icon (the toolbar icon was removed, as it's now redundant). Right-click it, and it offers a choice of sites that do useful things with geo information.
http://www.splintered.co.uk/extensions/geourl_0.3.xpi
oh, and marjolein: you can get the Link Toolbar extension for FF http://cdn.mozdev.org/linkToolbar/ (often wonder why this is not part of the core FF distribution)
Now that the extension is out, I am wondering whether every page in a web site should have icbm headers. (I thought that only the home page should have them, but this looks wrong with the extension...)
Seeing that no one had shared an update to the extension for Firefox 1.5, I decided to do so. It can be found at http://www.frozentruth.com/index.php?itemid=1563.