Vintage baseball cards, antique coins and rare comic books, originally bought for pennies, now regularly sell for millions of dollars, sending enthusiasts in pursuit of the next hot collectible: retro video games.

Interest in factory-sealed video games has soared in the past year, with some companies aggressively targeting collectors from more established markets. The hottest investments are games for the Nintendo Entertainment System, which popularised characters like Link, Mega Man and Mario in the 1980s.