This is why Singapore, which wants motorists to be aware of the social cost of their driving, has deliberately designed a device that lights up with the amount being deducted from the driver's pre-paid card each time the vehicle passes an electronic toll gantry.

ECONOMIST: A survey of commuting

With FSAs, employees can have a certain amount of money deducted from their paychecks, tax-free, for medical expenses.

FORBES: Fact and Comment

All three figures - the gross amount, the tax deducted (or tax credit) and the net cash received - need to be entered into the form.

BBC: John Whiting, tax partner, Pricewaterhouse Coopers