<center><img src="http://www.tmtuning.com/HOME/medienarchiv/bilder/606_a6-e-112.jpg"></center><p>This one looks kinda cool... and hecka cheaper than the audi factory one.

Or were there different ones offered for the allroad and S6?

Should be still available at the dealer, even if not on Audi's site, since a third party vendor made the item under exclusive sale contract with Audi (couldn't source direct even using my dealer's license number).
It's slick, painted OEM color and ready to easily install.

<img src="http://pictureposter.audiworld.com/8639/ati_icebear_mounted.jpg">

Perfect fit and installed in about 30 minutes, though I let it sit overnight to let the glue cure.

Does change the flow pattern over the rear window. In salty winter weather, I get more crap built up on the window, so it must be doing it's job and creating a negative pressure area under the spoiler.