Spaceflight aficionados, like many sports fans, love memorabilia. Space-related apparel, books, mission patches, stickers and other items sell at a brisk pace, and that’s just the bottom end of the market. The most valuable pieces are “flown” — meaning that they were either a part of or aboard a given mission. Many of those pieces are well out of reach for the common man – they are relatively rare and often quite expensive, at least for artifacts with certain authenticity. Others are affordable, at least to a dedicated collector, and can be bought for a few hundred dollars or less.