Riding in a car with my brother, he was in the back seat, he had a spider on him, just crawling. Somehow the spider got up to the front seat and i was afraid of it. The spider crawled down the window crack for a minute or so, then came back up and crawled across the roof of the car toward the passenger seat, i was extremely afraid, yelling for my brother to kill it and he finally did. We were still driving the entire time. The spider was big, brown but seemed to be harmless. Possibly looking for a way to escape also.