'ware cougars
 

But I don't agree that "bat" is used only with the negative. "She fluttered her eyelashes at me" and "She batted her eyelashes at me" are synonymous.

Joseph Wambaugh (in 'Hollywood Hills') agrees:

'When she said it, her lashes fluttered subtly, and Nate thought, an older chick batting her eyes at me?'

Jerome, here's what Longman's Dictionary of Contemporary English says:

2 not bat an eye/eyelid
To not seem to be shocked, surprised, or embarrassed:
"They started talking about sex, but she didn't bat an eyelid."

3 bat your eyes/eyelashes
If a woman bats her eyes, she opens and closes them several times quickly in order to look attractive to men

Of course, you may not wish to place much confidence in a dictionary that splits its infinitives.

But just do a search on the Internet. You'll find plenty of examples of the second meaning, even if many of them are questions from young girls seeking advice on how to flirt.

Mozart is OK. The operas are beautiful to listen to but about as dramatic as watching paint dry. You want an opera. Go to Joe Green.

Sorry, John, I can't agree. The last scene of Don Giovanni not dramatic? It's just about the most powerful thing I know in opera.

As for the Marriage of Figaro, I still maintain that it may be the most perfect opera ever written, both musically and in terms of its construction. But of course it's a comedy, so we can't reasonably expect Verdian (melo)drama.