While an unabashed love of classic cars is what really drives collectors to spend millions or even tens of millions on the hobby, the purchases—in addition to providing ego boosts and adrenaline rushes—often prove to be good investments as well.

Indeed, given the low returns on more traditional investment plays, some underwriters report collector cars are becoming even more popular these days as buyers view them as a way to park money in a relatively safe investment—while also getting a lot more enjoyment than what a stock or bond provides.

“We're the largest underwriter of fine-art collections in the U.S., and one of the trends we've seen is that when the parents pass, the children are liquidating the art collections and redirecting [the dollars] to other collectibles,  such as classic cars,” says Ron Fiamma, vice president and director of private collections for the Private Client Group division of Chartis.