Creating Volumetric lights from a mesh in cycles? is it possible / / how do i make an object give off "godrays" so that, for instance you can see it through slits in a wall? 

I'm trying to make this, (an icosphere with a sphere inside, the inner sphere gives off a blue glow) into a sort of "disco ball" is the best i can describe it. but i'm fairly new to anything blender and have no clue how to achieve this.


I read somewhere that the only object that could give off volumetric light is a spot lamp, but the thread was like 3 years old.

Edit: thanks for the help, what you said to do worked, just can't have a material output and lamp at the same time apparently :D but that's fine it looks good now!
Set the light inside the object and bring up the intensity.

For the world Volume add a volume scatter node. (usually the default value of one is way too high, set it to a smaller number)


(click on the image to enlarge)