I love the Overseers in Arthur C. Clarke's "Childhood's End." It's a bit contrived, to have an alien species come in, "fix" humanity (or at least nudge us into progressing), and ripe for "human resistance" backstories (fan fic, where are you people?) but I was inspired by one act in the book to conceive of something else the Overseers should have done.
In the novel, to show humanity they aren't fucking around -- and to instill in us some empathy -- they show up at a bullfight in Spain and make everyone in the arena feel intense pain.
In my story, I'd like an alien race to come down here, and whomever hasn't achieved "perspective" would be instantly transported to another part of the world where they have to fill another's position for, say, a week.
An example: some redneck who hates "the blacks" is transported to Somalia and has to be a fisherman. On the flip side, some badass warlord from Somalia is sent to Nova Scotia.
This is also inspired by the "empathy gun" from the filmed version of Hitchhiker's Guide to the Galaxy.
one man's journey into creating gibblybits