An anagrammatic poem is a poem in which every line or section of the poem is an anagram of all lines or sections of the same length. Anagrammatic poems are extremely uncommon due to their difficulty. They represent an interesting mixture of puzzles and poems.
A patchwork poem is a form of found poetry made of lines taken from different sources, and when assembled together they create an entirely new poem. Patchwork and cento are actually words used interchangeably when referring to this poem type. It’s just that patchwork poetry is essentially seen as the “modern” version.
A cento is, in essence, a collage poem because it consists entirely of poetic lines taken from poems written by other authors. Cento is in fact from a Latin term that means “patchwork garment”.