In case you didn't know it, your headlamps are aimed differently; the driver's side is positioned lower than the passenger side. No problem in the US, but when right-of-way lanes change in Europe, trouble. Audi's got a neat little fix.
The headlamp converter takes advantage of the adaptive headlight controls and allows for the beam pattern on the A4 Allroad to change to accommodate either left hand drive or right hand drive nations. It's not exactly a "why haven't they thought of that before" moment, as electronically controlled active headlights are pretty new, but still, an awfully clever feature you Europeans never new you needed. [GermanCarBlog]