Police scanners (assuming you can actually listen in your area - you can't in mine) are really cool.
I grew up with my dad listening to one, and he even heard something I was involved in one night, though he didn't know I had anything to do with it. Years and years ago, when I was in my 20s.
I was driving home one night, racing a little with the cute guy next to me, when a guy ran out of nowhere and I hit him with my car. Then he disappeared. I pulled over, the guys pulled over, then a bunch of people in leather and chains came running toward me off a side street. They asked if I had hit the guy, I said yes, they told me I had better get the hell out of there. So I did.
Then I got to thinking that the penalties were always worse if they had to track you down, and I didn't really do anything wrong, so I came back. There were now seven police cars from two cities, and I figured I was screwed. Told the cop anyway, and when I told him I thought I hit the guy pretty hard, he said "Good!" Turns out he had stolen a cop's baton and that's why he was running across the street. Then the cop took my ID, and told me to just go home and not worry about it.
I came home, and my parents are in the living room listening to the scanner. "Oh. glad you're home. There are some wild parties out there right now, and one where the guy stole a police baton and then got hit by a driver!"