What sort of mileage do you get out of a set of tyres?

[Second Best]

Was over at a friend's earlier to help him swap some wheels around on his family wagon (a VW Touran), he said the rears have been on the car since new, still had ~3mm of tread and had just ticked over 80,000 miles! He was only changing them as he had a spare set of alloys and had only just noticed the rear tyres were 11 years old so were due a change. 80k miles is pretty good going, I thought.

Meanwhile on an old works car I got a puncture on the way back from a service, where they'd changed the tyres too. It had covered 9 miles between tyre changes. grumpy

What's the best/worst you have got out of a set of tyres?