Black on Black, 136k miles, lots of extras.
The best part of this RS6 is the documentation - from Day one with the original owner, through June 2013 with the second owner, full report of every service done at Audi dealerships. From the day I bought it, it saw the inside of a dealership exactly once - to have new keys cut, programmed, and married to the Immobilizer. Receipts for all work below are included in the sale (and it's a thick folder).
Some spare parts from the previous owner, as well as a few that I've collected over the years, are included in the sale.
VIN ending 905530 - this used to be Tech_Gurru's beast.

Tech_Gurru was a service writer for Audi in the Portland, OR area - he had the following done thanks to his writing skills:
At 97k miles, the following were replaced under the extended CPO warranty:
Engine
Transmission
Torque Converter
Both turbochargers - Driver-side Turbo still on, Passenger-side replaced again since due to pothole damage.

He also installed KWV3 suspension, which is phenomenal!
He also had the original rims refinished in stock form.

Since he sold to me June 2013, the following has been done:

K-40 Radar Detector / Laser Jammer (not used in Virginia!) front/rear with license plate sensor / jams.
Carbon Fiber Interior from OCarbon
RNS-E with Bluetooth Module from NeoZawa, updated 2015 map pack, includes a 32GB SDXC high-speed card
Tires: PSS's on stock rims with ~5-6k miles on them
Wheels/Tires: Winter set- Stock wheels, painted lava grey, with Blizzak's mounted for ~3500 miles on them
Brakes: Front RS5 rotors (installed) plus resurfaced OE RS6 rotors (less than 10k miles), Hawk HPC pads ~3k miles ago
Brakes: Rear 2-piece ECS rotors (installed) plus resurfaced OE RS6 rotors (less than 10k miles), Hawk HPC pads ~3k miles ago
Suspension: Added Hotchkis sways F&R, tuned suspension settings for good road feedback but not scraping speed bumps
Body: Added Audi OE under-engine splash guard / air deflector
Body/Lighting: New Headlights in June '14 - still perfect and clear and bright.
Body: New front bumper in June/July '14
Engine: 6k miles or less on:
- Timing Belt/Water Pump/Pulleys/Tensioners/etc - full kit, gates belt
- Passenger side Turbo replaced
- Valve Cover Gaskets
- Cam Tensioners, plugs, seals
- Freshly rebuilt Alternator from Kaestner Auto
Engine: Less than 150 miles on:
- UIM Gaskets
- Aux Water Pump
- ALL vac lines under the UIM replaced with Silicone
- Injector O-rings
- EGT Sensors replaced
- PS Pump flushed/filled with BND Fluid kit
- Coolant flushed/filled with BND Hi-performance coolant
- SAI system removed, 034M block-off plates installed

EXTRAS:
Tire/wheel rack - wall-mounting, adjustable, still brand new in box
Tire storage bags - for the set not currently on the car, Audi branded, with felt pads.
About a half of a quart bottle of ACES-IV gas treatment
Other stuff I'm sure, just don't remember it all off the top of my head.

The beast is ready for viewing, but I will be pulling my insurance on it as of the day I take delivery of my Jeep, so no joy-rides. I'm sure I'm missing some / a lot of what's been done with this beast. Happy to talk about it with anyone interested. I know the thread is useless without pictures, but she needs a good wash and wax before she's ready for her close-up.

PS I know the KBB "value" - I also know that's for a beast that hasn't seen a wrench in the past 2 years. This is a well-sorted example that should be maintenance-free for the foreseeable future. Considered I've laid out well north of $10k in maintenance costs the past 3 years, that says something about how to value this car.

Thanks
O_E