Looks like the days of using a donut in a sandwich aren't over yet; Dunkin' Donuts is testing glazed yeast donut breakfast sandwiches in eastern Massachusetts outlets.
Granted, a rep tells us there aren't any plans to expand nationally as of yet, but the general media hype might imply at least a limited run for the nation. According to the statement, the Glazed Donut Breakfast Sandwich "features bacon and a pepper fried egg on a glazed yeast ring donut." A rep tells us that the suggested retail price is $2.99, if you are so inclined to track down the latest donut monstrosity.
Obviously, this isn't the first time a donut has been used in a savory sandwich, replacing the bread portion (they are both carbs, after all. We would prefer tater tots, but sure). The most infamous instance is Paula Deen's The Lady's Brunch burger, which uses a Krispy Kreme donut (although her sons claim it came from a Minor League gimmick).
And as for the reasoning behind Dunkin's donut sandwich? "We constantly strive to offer a wide variety of products to satisfy the needs of our guests." Seriously guys, tater tot sandwiches next.