It’s also about how firmly Americans are attached to their belongings, according to a 2009 study of storage by Carnegie Mellon University, Harvard University and the University of Virginia. “We do not know if people store their lava lamps because parting with them is such sweet sorrow,” the researchers wrote in an article in the Journal of Experimental Social Psychology. “But we do know that they store them because they like them and that they like them because they’re theirs.”