"Healthful supplement / present here where food's prepared: / it's the kitchen zinc"
"Sensations coming / from metallic reactions: / a zinking feeling"
"Gossips and costly / seagoing vessels conjoined / thus: loose lips, zinc ships"
"Rene Descartes finds / his elemental self: I / zinc, therefore I am"
"Enough! This is the / worst form of humor. I won't / zinc to your level"
"Shipwreck survivor / either saves his load or flees. / Which one? Zinc or swim?".
(Quotes taken from an article about the "DeCSS Haiku")
Update: And a Salon article about senryu errors.
Edit: Read this article and edited my post accordingly. Many of his complains of joke senryu don't apply to these (the puns are still funny without line breaks, or at least still puns), but the naming problem applies.