What's Fifty Percent of Nothing?

"I found myself staring at the business end of a gun."

That is virtually a cliché.

But what is the "business end" of a refrigerator?

If you can't work that one out, give a couple of examples of items with a business end!

I am a rare breed that is one of oldest American chickens.
I am a shark, a sparrow and a bat.
I am coffee and cachaça.
I am a French band; a Parisian Bal-musette dance; a Neanderthal who assists the title character in a Martin Mystère comic series; a live music venue at St. Lawrence University, Canton, New York; a song by Allen Toussaint which became a hit single by Al Hirt; a song by Augustus Pablo; a 1940 song hit by The Ink Spots.
I am also an island in Indonesia.

This one should give plenty of scope!

Question as per title.