Surfing around sites relating to Le Petit Prince, I was really pleased to come across the page on le roman de la rose on lepetitprince.com, and particularly the beautiful rose calligramme that it includes. I love calligrammes, and coming across this one online made me look for others. Probably the most famous creator of calligrammes was Apollinaire, and you can see some of his work here and here and here.
There are lots of sites with calligrammes by French schoolchildren. My favourite the one by Mme Cungs' class at Ecole Brieux, which includes an outstanding poem of / about the elephant, who never forgets, but is terrified by the mouse ...
Calligrammes Américains provides some really amusing poems based on "typical" American subjects ... like sports, the Stars and Stripes and, my personal favourite, fast food.