I want some of the experts here to chime in and tell me why this wouldn't work, just so I will stop thinking about it. You can get the 1320 tvs Audi supercharger from the newer S4s and S5s on ebay for like $800-$1000. It comes with an integrated intercooler alot like the LS9 or LF3 engine. First I was thinking you would just need to fab someway to mount it to the existing intake manifold with an extension for the bypass valve. Might not clear the stock hood. Another thing I was thinking was pull the intake manifold off, fab a valley plate with the water jackets, then fab custom runners from the intercooler outlets to the intake runners on the heads. That would probably be a lower height than using the stock intake manifold. I just like the idea of a self contained supercharger/intercooler combo. Another thing is the snout might need to be longer and where the throttle body on the Audi unit would hit into the firewall and need to be switched to the front of the car.
I couldn't post photos of it because they were too big. Google photos for a better picture of what I am talking about,