Not A Good Idea
The reason this light is there is because gas serves as a coolant to the fuel pump as well and you don't want to run your fuel line dry. Aside from introducing air which is not good you will destroy your fuel pump. Having said that, my Ford Windstar and Expedition from a full tank of 28 gals usually consumes about 24-25 gals when it starts to light up so I have like 50-100 miles to total empty.
Story replies
How do you know though? My gas light just turned on when I started up my car, and I'm in Chicago during rush hour traffic I have no money and I'm headed home; but idk if I'll make it. My house is only 12 miles from where I'm at in the city ( United Center ) and I live in Bensenville. But my gps says that'll take 37 mins to get home which is about 15 minutes more than the drive up here was. So with that being said even though it's only 12 miles it's a slow and long 12 miles to go on 290 westbound at 430 pm. Wish me luck and if you see me on 290 westbound in a silver Ford windstar please provide me with a small amount of gas or money to get gas lol praying I make it thanks for the info not sure if it really helps though. 50-100 miles but how much drivetime? That would be a better way to judge it I think. I'm just coasting barely using my accelerator if I don't have to I'm not pressing it.