Originally Posted by Sol
Do you have one of those special keys with the resistor on them?
Mine has that, and sometimes my car won't start. it just clicks. This is usually because it has a bad or dirty connection. Make sure that resistor is in good shape, cause without it, you can't start your car.
Um... if the VATS does not detect the correct resistor in your key, you will _not_ get a click from the solenoid; you will get only dead silence, and a "Security" light on your dash blazing away for three minutes before the system resets and lets you try again. Triggering VATS will kill the fuel pump and the starter-enable relay.
In the case of the original problem, I would suggest checking all battery cables at _both_ ends of each cable for loose or corroded connections. (Loose ones I think are more likely here.)