Yes, now you can light up your room with your Nokia 5800.
Thanks to Phone Torch application.

Phone Torch uses the lamp torch ability (LED of the camera) of the Nokia 5800 to light up the surroundings (in white or red)

There is other setting that you can customized such as turn the red light as default color.

Beside that it also can be used to send Morse code.

You can download the PhoneTorch here.