[ronk]

Spoiler

a light bulb

 

[MaralynMuir]

Spoiler

A light bulb

 

[Miss Chris]

Spoiler

A Lightbulb

 

[Fatal]

Spoiler

A Battery

 

[IJH]

Spoiler

light globe

 

[Mary_Again]

Spoiler

I assume everyone will answer a light bulb, but if it has a standard output with a regular power source it will have a standard lifetime. So it would need to be a "dimmable" light bulb capable of having a variable output and therefore able to burn "brighter" and be used up faster.
Being the daughter of a rocket scientist, the first thing I though of was a star, the sun being one. Heavier stars burn up their resources faster and burn brighter and thus have shorter lifes.
Of course one can't ignore a candle. Put a lit candle in a windy place, and if the wind doesn't blow the thing out, I believe it will also burn "brighter" and burn out faster.
After I submitted this I had a look at some other answers - light bulb as I expected. One said a battery - I don't think batteries burn "bright", they are only a power source.

 

[Bridget Williams]

Spoiler

COLOUR consuming LIGHT

 

[Jo Piper3]

Spoiler

Light globe

 

[<Stephen>]

Spoiler

A light bulb

 

[Mando]

Spoiler

A candle

 

[kiora]

Spoiler

A lightbulb

 

[Davo's Delirium]

Spoiler

Light bulb

 

[midgemills]

Spoiler

Fire.

 

[Kc1]

Spoiler

A lightbulb.

 

[violetsincas]

Spoiler

match

 

[SandyM]

Spoiler

A lightbulb.

 

[ozjp]

Spoiler

Candle

 

[derek hogben]

Spoiler

A light bulb

 

[Kovu08]

Spoiler

Light bulb.

 

[marni]

Spoiler

Candle