ALPHA
The Edget is the embedded widget. Currently the Edget is an online, cross-browser compatible, embeddable replica of the Converter extension for Firefox.
The Edget performs on the fly contextual unit conversions, timezone conversions and, when the weather is right, currency conversions as well. Here's a bare bones example so you can get an idea what this is all about.
Visitors who encounter the Edget in the wild can always configure their preferences, with or without an edget.eu account. Using the Edget without an account means you’re losing your preferences after every session, but that’s ultimately your decision. Create an edget.eu account if you don't have one, and/or set your Edget preferences. More information for users.
Webmasters can embed the Edget in their website—see the Webmasters section for more information. Short version: create an edget.eu account if you don't have one, register for an Edget key and embed the Edget in your site (you'll receive the instructions via e-mail when you register your website—it's a one-liner).
The Converter has been available as an extension for Firefox since 2004, and it has constantly evolved during this time. The Edget’s conversion brain is shared with the Converter—hey presto, instant, cross-browser online conversions!
Of course, the Edget is only available on sites which include it; if you want the conversion logic to go you still need to install the extension locally—but then you need to use Firefox, so it’s a mixed bag if you prefer a different browser.