Tom Snarsky
This will probably be underwhelming as a prompt, but I have a pet theory that 17 lines is the perfect length for a poem. So I invite you to write a 17-line poem; no other constraints. If you need another constraint to get things moving, I strongly encourage you to include a possum in it, or another animal who is (in your estimation) either underappreciated or unjustly maligned.

