Here's some TopGear maths: this new VW Golf BlueMotion has a 50-litre (11-gallon) fuel tank. VW claims it can achieve a whopping 88.2mpg on the combined cycle. Now, the average UK commuting distance is 16 miles, so you could theoretically travel to and from work for 30 days (an entire month, then) on one tank of fuel. One.
This involves you driving like James May on an economy run, but it provides evidence that somehow, using tenets of witchcraft banned in several American states, Volkswagen is giving you more for less.
About that "less". This new BlueMotion, now sitting on the MkVII Golf platform, emits just 85g/km of CO2 (down from the original 2007 BlueMotion's 119), and features low-friction piston rings, exhaust-gas recirculation, a quicker warm-up time, 15mm lower suspension, optimised airflow and low rolling-resistance tyres.
It drives just like a Golf. The 1.6-litre engine is grumbly when you accelerate with your Clarkson Hat of Power on, but otherwise it feels capable, punchy, flexible and - once up to speed - refined. Ditto the chassis and ride comfort. We managed over 70mpg, so if you're after a friendly eco box, it's very good at what it does.
1598cc, 4cyl petrol, FWD, 108bhp, 184lb ft, 88.2mpg, 85g/km CO2, 0-62mph in 10.5secs, 124mph, 1265kg, £20,355
Obviously, we'll tell you to go all out and get a GTI. But if you want to save pennies, this is a fine, well-sorted eco machine.