I've only just got my A3 (an '07 TDi Sport) and when one of the guys at work first saw it he said to make sure I always carried a litre of oil with me. He said he had one as a company car and it always needed topping up.
I thought he must've had a problem there, but on page 242 of the handbook it says oil consumption can be up to 0.5L per 1000km. That's a lot! My service indicator says 615 days until my next service, which by my calculation is about 9 litres of oil consumed .
From your experience, how often is normal to need to add oil?