Carmen Maria Machado, "Inventory" (Strange Horizons)
Alternate repetitions of "One man." or "One woman." to begin paragraphs. Sublime pacing and rhythm. 

Emma Smith Stevens, "Anthem" (PANK)
Alterations on repetition of "There are the boys...." and "There are the girls..." 

Jessica Barksdale, "Knock Knock" (matchbook)
"The bad childhood joke is".... starting each paragraph.

Justin Broukaert, "This Is What I Know About Being Gigantic" (Smokelong Quarterly)
"When you’re gigantic"... starting each paragraph.

Lucas Church, "Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo." (Booth)
Fantastic variations on the repetition of a single word, "buffalo."

Lucas Man, "Nondescript Love Story" (Wigleaf)

Marsha McSpadden, "Seven Since"  (matchbook)

Matt Bell, "Brother, There Is A Field" (NOO Journal)

Rachel Swirsky, "If You Were A Dinosaur, My Love" (Apex Magazine)
A tapestry of "If you were a dinosaur, my love..." situations.

Renee Gladman, "Five Things" (Paris Review)
Five paragraphs, each beginning with the phrase: "I began the day....." 

Rita Bullwinkel, "Phylum" (Bomb Magazine)

Roxane Gay, "I Am A Knife" (The Literarian)
The skilled, sparse deployment of "I am a knife." One of my favorite stories by Roxane.

Sara Levine, "Baby Love" (Necessary Fiction)
Strategic repetition of "I had a baby." as stand-alone.

Sherrie Flick, "Payphone, Notebook, Donut" (Drunken Boat)
"This was back when..."

Stephen Delaney, "How to Tell a Word" (New World Writing)