This is a common problem on our roads due to the (now remnants of!) construction activity! I'd changed 2 tyres on my Boxster, and had a screw in my Carrera tyre, but luckily it was short and had not penetrated the tread to form a puncture!
Recently on my way to the Abu Dhabi GP, I noticed a screw in the BMW tyre also, but this time plugged it since I will not be tracking that car!