Snowball (also called a Chaterism): A poem in which each line is a single word, and each successive word is one letter longer. One of the constrained writing techniques utilised by the Oulipo (Workshop of Potential Literature).
Given the mathematical genesis of the Oulipo and the interest in the movement among other programmers, I thought that someone must have created a program to generate these, and I was surprised that I couldn’t find one even after some pretty thorough Googling. So I wrote one myself. The C++ code is here.
It takes input from a text file which contains novels from Project Gutenberg, scans for word pairs where the second word is longer by one letter, and builds up a poem using Markov chains.
The poems in this post were all created by the program. They have not been edited.