I had a car stolen from my driveway several years ago in a nice suburban neighborhood. I know that this is overkill, but besides the ignition lock and alarm that comes with the SRT, I will have the following:

Revelo Anti-Theft device
The Wrap (alarmed club)
Rear wheel boot
Wheel locks
Locking gas cap
Lojack decals
Car cover with cable lock

Parked near front door of house under two 150 watt motion detector spotlights
Second car will always be parked behind it at night with a club on its wheel