Luckily there were several things going for me. I do try to keep a good distance from the car in front of me, esp on a highway, I was at an interchange between two highways so cars had to slow down for a turn and I was on the very left hand lane next to a median so it was very easy to turn off to the side patch of road between the median and the lane.
I immediately turned off to the side and stopped. I looked at the other gauges. They all read zero. I also noticed that all of the dash board lights were off. This seemed odd if it was just the gas tank being empty. I decided to try turning the engine off and then back on again. That worked! Everything was back to normal. The gas gauge read half again. Whew! A very nice driver let me back into the lane and I proceeded, nervously, to work; watching the gauges periodically, just in case.
Got to work without further incident. Hopefully it will only be a one time incident. Have no idea what happened. If it happens again, I'll have to take it into a garage to have it checked out.