Teasers--or Yawn-Factories

One of the lessons thrown at aspiring writers over and over again is the need to sell your story quickly.  Since all editors need sometimes to make decisions is the first line or two in short stories, the first paragraph or maybe page in longer works, you can't wait for the rest of the story to be good enough.  It's got to grab from the get-go.  But especially in the "query" first world, you've got to sell your story without using the actual story, to someone who is slammed with submissions, doesn't know you from Joe, and probably knows a heck of a lot more about the craft and industry than you do.
So you must sum up theme and conflict in one sentence, and it has to be compelling, interesting, and fresh.  And if you work on them too long or look at them too many times you'll go frikkin crazy.

Here are some of mine, short story and novel alike,mostly in the "light fantasy or science fiction" category:

An uprooted man joins a theater to recover from a recent loss, and must delve impossibly far into the world of his character to save the lives of the cast.

Two young people fight for their own definition of true love, despite the decidedly strange physics which stands in their way.  (That one is shooting for the odd genre of science fiction humor)

A storm-followed teenager runs away from home to rebel against her family's destructive secret, and must fight to keep her family and small Appalachian town in one piece.