What would cause a strange noise on the front left hand side of a 2001 Fiat Punto that sounds like metal is rubbing on something?

If it only happens when cornering the I would say that its a driveshaft - otherwise, more information is required I had the exact same problem. It turned out that on the inside of the left front wheel, the brake shoe pin on the bottom was locked. This made the brake shoe dig into the router. When the brakes were applied, the sound would subside because the brake shoe flattened out and went into a normal position. The answer is you need new brakes and routers.