The chart above (click to enlarge) shows the cost of 1,000 gallons of gas as a percent of per-capita disposable income, annually back to 1929, using EIA data for gas prices and BEA data for disposable income and GFD data for population (subscription required).
The retail price of gas was only about 20 cents a gallon from 1929 to 1946, but annual per-capita disposable income in the 1930s was only about about $400-500 (about $6,000 in today's dollars), so that a 1,000 gallons of gas cost as much as almost 49% of per-capita disposable income in 1933, and averaged more than 38% from 1929-1939~!
To reach those levels today, gas would have to sell for between $14 and $17 per gallon!
Bottom Line: When it comes to gas prices, it could be a lot worse. It was a lot worse. A lot, lot worse.
As an exercise, consider your life today, your house, your cars, your appliances, your electronic equipment (Blackberry, iPod, laptop, cell phone, DVD player, etc.), your life expectancy, your income, gas prices today as a percent of your income, and your overall standard of living, and now go back several generations or more, and compare your life and standard of living today to your grandparents, great-grandparents, or whatever generation in your family background was around in the 1920s and 1930s.
I think you'll find that there's no comparison. In most cases, you live like a millionaire compared to your great-grandparents, and in fact you have affordable modern electronic equipment like iPods, cell phones, and laptop computers (which are standard today even for high school students) that even a multi-billionaire couldn't have purchased in the 1930s! And as a percent of your income, gas today is still dirt cheap compared to gas in your grandparents' or great-grandparents' generations.