Yeap, it's ace! I was best man at a wedding in Tuscany a few years back so decided I'd drive down there in my old Mk2 Golf GTi 16v via the 'Ring, the Swiss Alps and the Italian Lakes.
Being on the track concentrates the mind somewhat and I was kacking it as I set of on my first lap. You don't have to rag it round so you don't need to trash your car.
If you treat it like a public road (which I think the Polizei do - think you can be prosecuted for causing an accident and all that) you'll be fine. Kacked it slightly less on my 2nd lap!
I was amazed at what was circulating - everything from my Golf with my wedding suit hanging in the back to a brand new Maserati MC-12 to a 53 seater coach full of school kids
to all the locals in their uber-modified Golfs and Jettas and people on their way home from work in Hertz rental jobs! There are loads of really good and interesting places to stay round there very close to the track. If you can get booked up for a lap in the BMW Ring Taxi (we tried but it was chocca the day we were there) and get driven round by someone like Sabine Schmitz in an M5 I reckon that'd be nuts but you have to book way in advance. A trip to the 'Ring has to be a must do for any car nut.