Went to Costco and found they have some nice very detailed Audi models for only $9.99. They are Maisto 1:18 scale (about 9" long) and are very high quality. I bought a bunch of them, so if you want one and don't have a Costco membership, you can get it from me for cost.

They have the Rosemeyer Concept and the TTR. It is metal with opening doors, independent suspension, and turning front wheels. The Rosemeyer is not my favorite car, but I'll buy just about any Audi model...especially at only $10.
<img src="http://pictureposter.audiworld.com/1436/pic00009.jpg" border="0">
<img src="http://pictureposter.audiworld.com/1436/pic00010.jpg" border="0">

The TTR is of very very high detail with opening doors, trunk, hood, wheels, suspension and so on. Nice desktop, eh? My wife digs it also.
<img src="http://pictureposter.audiworld.com/1436/pic00013.jpg" border="0">


I now have 3 Audi supercar models:
<img src="http://pictureposter.audiworld.com/1436/pic00006.jpg" border="0">
(BTW you can get the R8 model from the Audi dealer, and the Avus model from exoticar.com)

Still have the 1/43 Minichamps RS4 along with pretty much everything else.