BOSTON ( MainStreet) -- "I just don't get these kids and their ..."The list of items for the grumpy curmudgeons of the world to grouse about is growing shorter as young people go retro. Contrasting with the high-tech world we live in, many in their teens, 20s and early 30s are enamored and enthralled by items and activities rooted in past decades. Porkpie hats and fedoras are back atop heads. Burlesque shows pack theaters and clubs. Ear buds are being set aside for big, old-school headphones. Clove gum and hand-rolled cigarettes are once again the cat's pajamas. We took a look at five blasts from the past that have found a modern home among the nerds, hipsters and cool kids of America.