Those are worth money. I actually bought some old airchecks and there is a group of people around who collect them. It's slightly illegal because of copyrights on the songs but they are still available.
hah hah Money you say! That's weird. Weird!. My next door neighbor Mark from Australia used to roadie for rock bands. One day a DJ he was working with who was losing his job because the station was closing, took Mark's arm and whispered, "Hey, check this out!" He had ripped the playlist from the station from Day One and put it on a digital disk. Every top 40 rock-and-roll song from the last sixty years, all on one I-Pod. Thousands of them in order of appearance on the charts. Mark knows what his friends want for Christmas. It's awesome. No doubt if the owners of the station found out they'd be angry as Hell.