Predicting the future of the collectible car market is a tricky game. Some cars regularly make everyone's list of future classics, but those are no-brainers. Obscenely expensive supercars, beautifully designed luxury coupes, and beloved sports cars are easy picks—no one will be shocked when the Scion FR-S and Mercedes-Benz SLS AMG are sought after decades from now. Figuring out which ho-hum family cars, sales failures, and throwaway compacts will be loved makes for fun conversation. Nobody who bought a Ford Fairlane in 1966 thought it would one day be highly prized. The same goes for the Impala, Microbus, Datsun 510, and many other offbeat collector cars. With this in mind we've sifted through the past 20 years of mainstream production cars in an attempt to pinpoint the potentially valuable vehicles that might be affordable today—or in your garage right now. What are the factors we're using to make our picks? Novelty, rarity, historical significance, and, most important, the potential for nostalgia.