I'd like to see a Hawkeye/Widow movie. Doubt it'll ever happen since both will likely just be relegated to cameos in the bigger core character movies, but I think it'd be a great espionage flick and add another layer to the Marvel films.
I want to see a Hawkeye movie. Don't really care about Black Widow so much.
You know though, they showed on Tony's computer screen Hawkeye and Widow fighting together, though I can't remember just where at the moment.
Maybe a pre-Avengers movie tie-in?