Re: fuel saver
Actually, they're often quite good fridge magnets! I still have some of the research ones on bits of string for fishing ferrous stuff out of tight spaces!
Something to bear in mind on the aircon though. Use it for at least 15 minutes a month or the face seals on the compressor dry out and it starts loosing gas. Also the lubricating oil that's mixed with the refrigerant starts to separate out. Most manufacturers have something in the handbook about keeping it used. Don't know about the 166, the 15 minutes thing came from a Peugeot handbook. The amount of fuel you save will depend on how much work the system is doing. On a day like today with (up here) 6 degrees ambient air temperature, you'll hardly save anything. On a 30 degree day with a car full of people, you'll make a significant saving - probably more than 2-3 MPG!