Online live police and fire scanners (courtesy of another ETS member):
http://www.radioreference.com/apps/audio/?mid=18We recently had a lengthy thread about home security.  The thread title was something about someone's house being "cased."
For a sliding glass door:  charlie bar and alarm.
Centrally-monitored alarm system and a big dog are the big deterrents to home invasion/burglary, according to DC police.  
DC police also advocate bars on doors and windows but that would look odd outside the inner city.  Yes, more law-abiding people than criminals in DC are living behind bars....