If your goal is to make enough money to retire early, prioritize earning potential over job satisfaction, since you plan on getting out of the rat race early, anyway. Consider the types of jobs that pay extraordinarily well in exchange for hard work, little psychological satisfaction, and a punishing lifestyle, such as investment banking, sales, and engineering. If you can keep your expenses low and do this for about 10 years, you can save a nest egg for a modest but youthful retirement, or to supplement your income while you do something you really love doing but doesn't pay much. But keep in mind that delayed gratification requires clear goal-setting and strong willpower.
Websites like Survey Junkie will pay you a decent chunk of change for the low-maintenance, borderline mindless task of completing surveys. Companies want to understand consumers better, and one way they do that is by compensating survey-takers (a.k.a. you). Most surveys pay between $0.50 and $1.25, and many of them take less than 5 minutes to do. You can read our full Survey Junkie review for more info.