With the amount of snow currently blanketing the UK, it might be unrealistic to expect public transport to run on time, but in some countries it's such a precise science there's even an iPhone app to help ease your journey.
It's called Wake Me Shake Me Train Alarm and it comes from Japan, where they say you can set your watch by the regularity of the trains.
Knowing where to get off
While that's not quite true, departures are so reliable many people happily sleep in their seats and are so accustomed to the exact duration of the ride they wake up and leap off at the right stop as if by magic.
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For those unlucky enough not to be perfectly tuned in yet - or on those hush-hush lines in Tokyo where the dirty words 'running late' are whispered only in hushed tones – Wake Me Shake me combines the iPhone and GPS to avoid unexpected lie-ins.
The $2.99 (£1.85) WorLD Software app is beautiful in its simplicity – simply tell it the station where you want to get off, set the alarm radius and nod off.
When the app hits the radius – the default distance is 500m from the destination station – an alarm vibrates the iPhone in your pocket or hand and off you go. In theory, that is – it makes no claims to be able to rouse those who've had a little too much Christmas spirit.
While Wake Me Shake Me may sound a little frivolous at first, the prospect of being late for work or having to grab an expensive taxi ride home after the last train has overshot your destination makes the price seem an absolute bargain.