One of my favorites is Movement and Distance (http://archiveofourown.org/works/522335) by cat_77. Rated: Explicit. Summary: Sometimes separating yourself from a situation isn't enough. Sometimes you need to move to see where you've been. I love the Clint/Natasha relationship in this one. And -- Wingfic!

Also check out cat_77 's Fine Print (http://archiveofourown.org/works/602021). Summary: Always read the fine print. Or the one where Natasha is a Disney Princess. This one's just really clever and Natasha gets to show off her business aptitude.

Check out cat's other fic too, she has a neat series going, Respiration (http://archiveofourown.org/series/42997), it's not Clint/Natasha, but they do have a great friendship in it.