There is a growing underground force of pop labels releasing music on nontraditional formats. Of these formats, two prevalent ones, at least in the lo-fi pop and twee pop arenas, are cassette and the 3-inch single. Being such a strong fan of the genres that release via these formats, one would think I would have the ability to play them when they arrive in my mailbox. Unfortunately, I do not at this time. (But boy do I love receiving them!) WeePOP! Records releases via the …