I used to cross streets when it came to some people. My brothers and sisters and I would all be walking home from school, and I would see this person coming towards us on the same side of the street and I'd stop for a minute, then I'd cross over to the other side of the street and take my siblings with me. Once it was so bad that I didn't even wait to get to a stoplight, I simply stepped out into traffic in an instinctive drive to get away from the thing I saw, almost got hit by a car too. Since then (I might have been 12-15 years old), I've learned to go running to God about people instead of crossing streets, a far easier method by which to deal with something unpleasant to you, far safer too) I still walk by people today and just "know", one of the things I pick up most is any kind of deep sadness and what it is.
There are some days when I pray about 25 times for people I've never seen before/don't know but just knew what was wrong. I've done the same online too, so I guess you don't have to be close or even see the person in some cases. However, I rarely ever tell anyone what I might or might not discern about them, most of the time there just doesnt seem to be any need to. I tend to feel very deeply for the problems of other people, I guess I'm a healer at heart and the gift of discernment is a good way of getting to the root of the problem to heal the person.
Once when I was walking down the street getting off the city train, (it was very crowded in downtown) I walked pass this man laying under some benches (a normal occurence since i live in a city and there are alot of homeless) well something just said to me "stop" and i was in a big hurry because I thought I'd be late for my connecting bus but I stopped. Everyone else was just walking pass this man, some were literally stepping over him and just going about their business...but me I stopped and I looked at him....and there was nothing there but miles and miles and miles of blackness, by blackness I don't mean darkness or evil, almost like when you shut the lights off at night to settle down to bed or when you close your eyes to sleep, not pitch black. There was also this odd stillness, almost the way it would feel if the ocean suddenly stopped swaying, and the currents stopped moving. It was obvious to me that the man was no longer living. It was the first time I'd ever felt led to pray for someone who was dead, but I don't know if I was praying for him or those that might also end up like him.
Anyways thats one story enough about that, all in all discernment can be a handy gift, however it can be a very confusing one as well and if not used according to God's will it can also be very damaging. I must say though that I've never discerned a spirit in anyone truly a child of God, always just around them hovering sort of......however I have discerned them without being on or around a person sort of just there, probably waiting for a clean house to invite them in, usually this is when i bother to tell someone about it, its usually a warning for them not to do something....odd thing is they rarely listen and it usually happens anyway. Another story there about a friend who knew what I was warning her about, knew exactly what I meant but went ahead and did it anyway.