Iconic to me and, because the sleeve design looks like the music sounds: (this might be a retrospective sensation, though...)
Level 42's True Colours album and single releases, Kajagoogoo's The Lion's Mouth, Genesis' Invisible Touch Album, Peter Gabriel's Us album & singles and, again, Simple Minds' Street Fighting Years album, singles and the great Themes box set series.
Totally forgot they did that! Yeah, Real World - that's an iconic graphic to me. I mean, I can't imagine Peter Gabriel's "Passion" cover WITHOUT those colour blocks - wouldn't look the same (or as good)!