Toy maker Hasbro first launched the Transformers as a toy line in 1984, and the vehicles that transformed into robots remained popular through the early 2000s, eventually spawning cartoons and blockbuster movies. However, when it comes to how millennials can invest in nostalgia, if you have any plastic or metal licensed character lunchboxes from the ’80s or ’90s, they might be worth a few hundred dollars. The older the lunchbox, and the more popular the character, the greater the value — with metal lunchboxes from the early ’80s selling for more than plastic models from the ’90s.