I never need a clock.
I'm outside with my dad starting at about 3:30. After a while, he asks me what time it is. I tell it's about 4:30. For some reason, I can usually judge how much time has past, so he turns on the radio outside and it's 4:28. I was like w00t. This has happened a couple time beforehand.
Is that a Ni or Si trait, to know what time is it, within a couple minutes.