Tonight at 8:30 PM is Earth Hour—an hour where hundreds of millions of people, businesses and governments around the globe will turn off their lights to help the environment.  YouTube is getting involved in a unique way, but letting users flip a light switch on video pages to darken the screen.

Flip the switch in the top left corner of YouTube video pages today and all the white areas of the screen will turn dark grey so you can watch in a more environmentally friendly fashion.  Personally, I rather like the dark look and hope this option will be available beyond this evening.

Earth Hour Global is also running a fun challenge on their YouTube channel at youtube.com/earthhour.  The ‘I Will If You Will’ challenge challenges you to promise to do something if you get a certain number of people to do something good for the environment.  For instance, Earth Hour Global asks, “Would you get a panda tattoo if 100 friends agreed to recycle?”

You can create your own challenges to get other people to sign up for Earth Day or take part in other activities to help the environment, or you can accept other people’s challenges.  Betina Gozo will eat a three pound, two foot long gummy work in 1 sitting if 10,000 people sign up for Earth Hour.  What would you do?