Dan: I have made pet caskets (yes I said pet) before for birds, hamsters, bunnys, you name it. The construction would be guite the same for a pen box. Figure out the length and width you need to fit the pen into the box. Draw out your casket shape on a piece of graff paper. Transfer or glue this to a length of 2x4. Cut out the shape of the coffin on a band saw. Next turn your coffin on it's side and slice off a 1/4" of the top, turn it over and do the same on the bottom. Mark these as you cut them so you know which way they go back together. Turn your coffin right side up and mark off a 1/4" wall thickness all the way around the inside of your blank. Go back to the bandsaw and, starting from the end, cut out the inside of your blank You now have a bandsawn box in the shape of a coffin. Sand the rough edges an a sheet of sand paper of a flat surface. Glue the cut end back together and clamp tight. Glue the bottom back on. Sand your outside surfaces, finish, and install interior. I finish the inside with silk, velvet, or use a flocking kit. You can buy hinges and findings at most craft stores. Look for 2x4s with small tight knots in them for interesting effect. For a more modern looking castet, use moldings or exotic woods, round the tops, carve them, or put small wooden or metal crosses on the 2 piece lids. The possibilitys are endless. Jim S