Some poetry is "free verse" but many poems are crafted by following some sort of form or constraint--they might be sonnets or ballads or pantoums or squares, or possibly even a newly invented form. From poet Tiel Aisha Ansari I learned of a "syllable sestina challenge" from Wag's Revue. The desired poem contains six lines and only six syllables, which are repeated using the following permutation-pattern (the same pattern followed by the end-words in the stanzas of a sestina):
Here is a syllable-sestina entitled "That's a Wrap" by Ansari. This and also other responses to Wag's Revue's challenge may be found here.
Cuts, if loose, tingle would.
Woodcut ills: if tin glows,
lose wood thing. Cut civil
Thing: ill-cut, loose wood sieve.
Sifting would all lose. Cut.
For readers unfamiliar with the sestina format for a poem, this Wikipedia link gives the history and a definition, and the external links at the end of the article offer numerous examples.