Last week I got the dreaded phone call from the wife.  The car has a problem on the way home from work. As stated above it is a 2005 GT we have owned since new. She was on the X-way and the check engine (MIL) came on.  Then the cascade of events followed:
Data center: Oil pressure low, Fuel low.  Both gauges registered zero.
The radio stopped working
The headlights went off.
Parking brake light was on.
Whe she got home I saw her brake lights were not working except for the cyclops.
She got off at the first exit and into a parking lot. She knew the fuel tank was full.  She checked the oil dipstick and oil level was normal. 
She got back in the car and the gear selector would not come out of park (auto trans)  She got out her glove box screwdriver and hit the lock release and got it in drive and came home back roads.
The engine was running normally.
Next day I read the codes and got P0463 and P2068 (A & B fuel circuits high)
I talked to a couple of EFI familar people and we decided there must be some kind of major grounding problem for all these things to happen at once.
I cleaned and retightened all the grounds I could find.  So far,  all systems normal and no MIL atter a week of normal driving.
I thought this might help someone avoid a trip to the dealer.