In Ranch Dressing - Why do Americans love it so much? Slate.com reviews the rise of ranch dressing as America's number one salad dressing. However, the article also notes several other uses for ranch, including as a dip for french fries and buffalo wings, and as a topping for hamburgers.
One of my college roomates experimented extensively with ranch dressing in the 1990s, applying it to a host of different foods. He called it the "universal hilbilly condiment," because of its versatility and popularity at family picnics. The Slate article confirms his theory that hillbillies love ranch: "And numerous Pizza Hut franchises in the South began offering cups of ranch alongside their pies, after a few franchisees discovered that teenagers were dipping their slices in the dressing."
One of the oddest uses of ranch I saw was on spaghetti. We were running low on Ragu, so he poured what was left of the red sauce on his spaghetti, mixed it up as best he could, then poured on two or three tablespoons of ranch. He swore it was delicious and ate his spaghetti that way from then on. When mixed up, it had an odd pink color, so I refused to try it. Then, about a year ago, I was out of spaghetti sauce at home and I tried it. He was right. It's actually very good.