Symphony.

This is an extension that adds a few global params containing basic information about the user agent.

You can download it from google code:

http://browser-extension.googlecode.com/files/browser.extension.v.1.0.zip

OK so it provides;

$browser  
$browser-version  
$platform  
$platform-version

It would be great if this is extended with the language settings of the browser, so you can serve the preferred language.

We usedto have this

and even country detection

Or is this already achieved with the browser headers extension ?