If you're on Facebook, or probably any other social media, you've probably seen or heard about the "No Gas Day" event. After thinking about it for a whole 3 seconds, I can firmly say: "what a dumb idea."
If I were a gas company, I would have dropped prices really low today (maybe 20 to 40 cents), then tomorrow, raised them $1, purely out of spite of the ridiculous notion that one day of your "protest" was going to make a huge difference in our profits. Gas companies are well aware that you don't need gas every day, but they know you need it often.
Also, someone made the point to me that "it's about disrupting the schedule." If that were the case, then today they would have an odd "lower than average" sale, and tomorrow (or a few days later) a "higher than average". It doesn't matter if you buy it today, tomorrow, or next week; you still bought it.
If anything, find better ways to "stick it to them". Buy more fuel efficient cars, walk when you can, use a bike, carpool, etc. Changing your lifestyle will make a difference, not just taking a one-day stand.