If I go out on a bright day I have to look straight at the floor. It makes me squint and hurts my eyes if I even look straight ahead.
Bright sunlight also makes me sneeze. Pretty much every time I walk outside when the sun is not obscured by clouds I will sneeze, but looking at the ground does minimise the chance of me having to sneeze.
I can look at tungsten lighting fine, provided it's not ridiculously bright.
This is a little off topic, but I actually don't really like natural light much. I always have the blinds in my room shut, I much prefer to be in tungsten lighting than have light shining through the windows. Daylight seems cold to me, for some reason, and I'd rather avoid it if possible.
It's not too bad if I'm outside, but I really don't like daylight inside, it bothers me.