Here are some ways you can listen to police, fire, EMS, aircraft, and rail broadcast for free without a police scanner. You can listen to it on your cell phone or on the computer.
Online / Desktop
Go to Broadcastify to listen in on what is going on in your town
iPhone / iPod / iPad App
Search and download the 5-0 Radio Police Scanner Lite for free
Android App
Search and download the Police Scanner Radio Scanner for free
Reference Sheet
Link to Police Scanner Code Reference
187 - Homicide
211 - Robbery
311 - Indecent exposure
390 - Drunk
510 - Speeding or racing vehicles
586 - Illegal parking
604 - Throwing missiles?!