The best defense if no defense I figure:- Don't give the thieving 
    bastards anything to steal, of course this is easier said than 
    done.  I've had people break in to my bus for a measly 78 cents!!! 
    Luckily no windows have been broken so far, I'm considering 
    leaving it unlocked though.  If you insist on leaving valuables in 
    your van I suggest that you gift wrap each item and attach a brief 
    description of what's inside to the wrapping. This will assist the 
    "shoppers" in moving though your van faster, freeing up their time 
    and yours.
    
    As for car alarms I fine people tend to ignore them rather than 
    rush over for a look see.  Isn't human nature wonderful?  
    
    Eric