Whistling up a pig's ass 

This picturesque expression was originally used by Rednecks in the USA, but has achieved wider usage due to combined operations of US and European troops. It is used to describe something that totally futile, a waste of time and effort and something that you do not wish to do. By extension it can be applied to mean a person who is a waste of time and effort, someone with whom you do not wish to associate and whose existence can only be described as one of nature's biggest mistakes..

Malcolm's made another great and glorious cock-up, that asshole really is no more use than whistling up a pig's ass!

Whistling up a pig's ass by Croatalin April 26, 2014

Westinghouse kids 

The bitches that go here be dressing like they rich. Bitches be fake fighting over them fake rich ass niggas who really ain’t shit. Teachers be mad annoying. Seniors be tryna finger freshmen girls on the third floor stairs and shit. Like what the fuck?

Them westinghouse kids be tryna dress like they on fashion runway like what the fuck?

Westinghouse kids by Realchicagonigga September 27, 2019

WHISTLING RODRIGUEZ 

WHEN A LATIN GUY GIVES YOU A HAND JOB WHILE WHISTLING SALSA MUSIC

DURING MY CRUISE TO ENSENADA MY WAITER OFFERED ME ME A WHISTLING RODRIGUEZ

WHISTLING RODRIGUEZ by JAILWILLY August 21, 2011

just to be sure it's Westinghouse 

Means the same as the phrase, "just to be sure"; the "it's Westinghouse" part originated from television commercials for Westinghouse Electric in the 1950s, who's catchphrase was, "You can be sure, if it's Westinghouse".

{Craig}: Hey Paul, did you remember to charge your wheelchair today?
{Paul}: I think so but let me check just to be sure it's Westinghouse.

just to be sure it's Westinghouse by Telephony July 28, 2014

whistling-canadian 

a blowjob from a 5 dollar hooker with maple syurp in her mouth

Dam white boy wishes he could get a whistling-canadian.

whistling-canadian by abe the jue June 5, 2007

Whistling Gandalf 

Verb: When a man with a long beard gives head and wraps his beard around the shaft.

Dude, Gimli gives the best whistling Gandalfs.

Whistling Gandalf by WalksN2Mordor March 7, 2017

synthetic whistling 

Not all dissimilar to synthetic clapping, synthetic birds, synthetic finger popping, etc.
It is the sound of human whistling created solely by synthesizer hardware or computer software synthesis. Most frequently heard on TV commercials for various & sundry household products; especiall.

No actual lips are injured or otherwise harmed when synthetic whistling is employed.

The Take Control margarine advertisement from the turn of the century had this horrid synthetic whistling in it. Made me want to throw a large tub of frozen Gold & Soft margarine right through my TV set's boob tube and then suck up all of the glass with a bagged upright vaccume cleaner so that the cat doesn't cut her paws on it! :-(

synthetic whistling by Telephony May 8, 2015