I don't know if this is creepy exactly, but it was really strange and happened to a good friend of mine.
She is with her husband camping in an area with absolutely no cell service. They own the land and their travel trailer stays up there all summer and they go on the weekends and what not. It is a place they have been many many times and they have never had cell service there.
One night they're sitting outside at a table eating dinner and they hear her cell phone ringing in the cab of the truck. Because it does not have service they never even bothered to take it out of the truck. She answers the phone and she hears her sister's voice say "Chelsea has been in a car accident. They're taking her to Desert Valley Hospital." And the phone cuts out.
She looks at her husband and tells him what she heard. They basically lock the door to the trailer, not putting the outside table or anything away, and start driving.
They got to the hospital in about three hours and her niece passed away within an hour. Later talking to her sister she finds out that her sister didn't even hear her say hello. She didn't think she actually got through.
They've never had the phone ring while they were camping again. There is absolutely no service.