Risky Business Dance

A character who is home alone dances around like a fool, singing into a hairbrush. Usually a celebration or declaration of freedom, but sometimes just a way of showing that a character is happy and positive. Very common right after a character has scored a date with their longtime crush. Named for the famous scene of Tom Cruise dancing in his underwear.

Examples of Risky Business Dance include:

Film

The Guru (2002), the eponymous main character played by Jimi Mistry auditions for a movie while dancing to the song in underwear
Mrs. Doubtfire
Never Been Kissed In a Famous Couples prom theme, Rob dresses up as Cruise in his dance scene.
The trailer for the first Garfield movie.

Live Action Television

Geoffrey on The Fresh Prince of Bel-Air dances through the Banks' living room.
On News Radio, Jimmy James does it at Dave's parent's house where he is hiding from the police.
In Living Color did a Dead Baby Comedy version, where the Menendez brothers do the dance while wielding rifles.
Arrested Development, "Development Arrested", Ted is dressed like Tom Cruise (sunglasses, collar up, no pants) under the "Risky Business" banner. He can be heard saying "I couldn't see through the glasses and I slid into the ladder", implying he (unsuccessfully) attempted to re-create the famous "sliding in front of the stairs" scene from the movie, in front of the ladder.
Lizzie McGuire, Season one, episode 10
The Lone Gunmen "Eine Kleine Frohike"
The Nanny: At the end of "Canasta Masta", Niles does until C.C. walks in on him.
Saturday Night Live, Season 11 (1985-1986 season), episode 9 (hosted by Ron Reagan, Jr.) and Season 19 (1993-1994 season), episode 7 (hosted by Nicole Kidman).
Veronica Mars, "Ruskie Business" (which also features a character named "Tom Cruz")
Parodied in Scrubs like so.
ALF "Looking for Lucky".
Married... with Children "Breaking up is Easy to Do, Part 2".
The Office Michael Scott, making reference to Risky Business, instructs an employee to "take your pants off, run around."
Saved by the Bell, when Zack, Slater and Screech had a sleepover (except it was "Barbara Ann" by The Beach Boys)
At the 2000 MTV Movie Awards, Ben Stiller, as Tom Cruise's stunt double "Tom Crooze", recreates the opening slide, sliding hard against the wall.
Tracker Nestov, dancing around in his underwear to 'Old Time Rock And Roll' after tying up Mel and Cole. He gets interrupted by an annoyed Zin and his Mooks.

Video Games

The intro movie to the computer game of Nightmare Ned features Ned doing this briefly.
The recent ad campaign for Guitar Hero.
- The ad for Guitar Hero Metallica starts out this way, but no one appears to dance. They were tied up by the members of Metallica, who announce "Not in our commercial" before blowing up the house.
  - Used again for the ad for Band Hero nonetheless.
  - For an extra layer of bizarre, the actors doing the parody are all famous college basketball coaches.
  - ... and for an extra layer of Fan Service, GH5's promos had Playboy models doing it.
- While the ad campaigns for Guitar Hero World Tour had the song featured, it didn't come out as DLC until well after the game was released. Needless to say, many shouts of joy were heard when players saw the lead singer slide across the stage to the microphone when playing the song.

Western Animation

Kyle of South Park does this when his parents are arrested for child molestation, leaving him to take care of himself.
Spoofed in King of the Hill: Bobby slides in his underwear just as Luanne is watching the scene on TV. Turns out he hasn't seen the movie.
Doug
The Simpsons "Homer The Heretic" (dancing to "Who Wears Short Shorts?" instead of "Old Time Rock 'n Roll")
Duckman "Apocalypse Not"
Briefly in the Kappa Mikey episode "Mikey Impossible"

Others

Rudy does it in this Kevin and Kell strip... except he forgets he isn't quite home alone.
Something So Right did it with two of the exes.
Another of those parodies was played during the NCAA Basketball tournament in March–April 2009. It included coaches Mike Krzyzewski, Rick Pitino, Roy Williams, and Bob Knight as the lead singer - all dressed in the standard pink shirt and boxers.