Well, I am not off to Pennsic yet (next Saturday), but the theme of "So Long and Thanks for all the Fish" was what I was given as the idea for Arisia (a scifi con in Boston) that I was artist guest of honor at back in 2001. That is a hard "theme" to try and do art for. The T-shirt ended up with a merman in a space suit and the con badge was this "Space Dolphin". The design was black and white for them to print but I did a colored version which I really liked. This is how it came out with the wording removed. I think it was about 3 x 5 on Bristol paper in Pigma marker. The colored version is watercolor colored pencil and acrylic.