In case you don't have your smartphone app handy, the taps are equipped with LED lights to show the water's filter status as well -- blue means clean, yellow means not so much and red means you should probably get a new filter, pronto.

ENGADGET

Feeney fouled Arason as the keeper cleared just before the break and the resulting yellow card means he is banned for the trip to Sweden next month.

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The Met Office's yellow warning means "be aware".

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His replacement Carles Puyol picked up a yellow card, which means he will be suspended for the return leg.

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The Met Office has issued yellow warnings, which means be aware, for snow in parts of Scotland, the north-east of England, Yorkshire and Humber and the East Midlands.

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Roza Otunbayea, leader of the Ata-Jurt (Fatherland) movement, who was denied registration as a candidate, insists that yellow is the colour: it means ready for change, she says, as in a traffic light.

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In the west, a yellow warning is in force, which means to be aware of potential disruption.

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Brunt then picked up a yellow card for a clumsy tackle which means he will miss the qualifier against Slovenia.

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Yellow Blue Bus is all about the love (Ya lyublyu vas means 'I love you' in Russian).

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