When driving in daytime (In Britain) and it's very dull, raining or foggy I generally put dipped lights on, as do many other drivers. The Highway code recommends this, but you still see situations where 95% of drivers have lights on but the other 5% seem to be totally oblivious to the fact that all the cars they can see have their lights on.

Someone told me that in some countries this is mandatory in winter (say November-February) - is this the case? I know that Volvos have their sidelights wired to come on with the ignition so presumably this is a Swedish requirement.

The military seem to use their lights the year round (I think this originated with the US Army or the Wermacht) . I was wondering if any countries require everyone to drive with lights on all year round?