In the testing literature, the term load testing is usually defined as the process of exercising the system under test by feeding it the largest tasks it can operate with. Load testing is sometimes called volume testing, or longevity/endurance testing.
Keep your taste buds awake, drink an energy drink. This may raise your level of alertness for a reasonable amount of driving time. Suck or munch on an apple, orange, or even a lemon to keep taste buds awake. The more tangy the food item the better. (Pull over somewhere safe before eating anything that you can't just pop in your mouth, however.
There were several attempts in a world history to achieve a record of being awake longer than anybody else. Randy Gardner, a 17-year-old student from San Diego, California, the USA, managed to stay awake for 264.6 hours (that is 11 days and 24 minutes) in 1964. His record entered The Guinness Book of Records.