Well before taking the gig as the writer of Marvel's Winter Soldier series--in fact, well before Winter Soldier even existed--writer Jason Latour pitched an Invaders miniseries to Marvel. He recalls it being sometime around 2003 in a post on his blog.
"It of course would have heavily featured Bucky Barnes and was even going to be told largely from his POV," Latour said. "The response was pretty good, even though I doubt it would have ever been made. Here's some art I did way back when--At the time I was putting it together I was 25 or 26 and still failing miserably at aping Mike Mignola's art. Man, that Human Torch sucked."
He's posted the cover and some pages from his pitch on his blog, mostly some war scenes that set the stage, but Captain America does make an appearance on the last page. "The Invaders aren't really in my plans for Winter Soldier, but I still think there is a world of potential there, so maybe one day," Latour said.