Its been a pretty crazy ride with the RS6 which I truly did love. I didn't go far - I'm in an 2012 A6 3.0 now. Not as fun as the RS6 but with a change in work location I was commuting the RS6 year round and between gas, misc repairs, and potentially expensive time bombs (TC/Tranny) I decided to get out while the going was good. I've doubled my mpg and I have CPO warranty. Hopefully I'll be looking at an RS* car in 3-4 years as a CPO car. This was really is one of the best communities I've been exposed to. There are a LOT of very smart and helpful people here.
Few pics of the A6 are here: http://www.dea.net/a6.html
The few things hanging around from the RS6 (all pictures at http://www.dea.net/rs6/ )
Full set of OEM Audi Winter Floor mats - $80
Full set of wheels + an extra - $400
Set of tires the A6 came with 245/45/18 (I used OEM 18" wheels for winter tire setup and picked up new 20" A7 sline wheels so needed 20" tires) - $400
MyGenius from DimSport for loading Eurocharged tune (will need separate tune from them). I think some other tuners may also use it too. - $250
BlitzSafe AUX adapter for adding headphone jack - $50
I'm in the Boston area and can arrange pickup/dropoff/meetup. I could go as far as Hartford/Albany for a meet up. Of course I can do better pricing based on what you wanted. Shipping would be at your expense and I'd rather not but would.