Keep it Clean
These are the days when I used to run out of windshield wiper fluid and would have to pull over, dump water or throw some snow on the windshield so I could see. Then one day, there was a buy one get one deal on the fluid. It was then I realized if I had an extra bottle in the car, I wouldn't continue to have this problem. I'm a little slow like that sometimes.
The point is, always have extra fluid in your car. You'll thank me later.