Originally posted by Dwarflord:

Workbenches have a radius (same as their build radius) that prevents mobs spawning inside of it. Standing torches, campfires, other crafting benches, and probably some other things I'm missing also do the same, but you can't see their radius. I like to use standing torches as they are cheap and don't take up much space. They don't have to be burning to work.

I read about workbenches... It doesn't work for me. I placed them problably everywhere, around my base.