Joseph Gordon-Levitt and Tony Danza are attached at the hip these days.
Let's break it down: First, Danza co-stars in Levitt's directorial debut Don Jon, which hits theaters Sept. 27, playing the father of Gordon-Levitt's porn-addicted character who tries to move beyond the obsession and find true love with Jersey girl (played by Scarlett Johannson).
Second, Gordon-Levitt highlights his bond with Danza while lip syncing to "Tiny Dancer" on Late Night With Jimmy Fallon this week, at which time he mouthed, "Hold me closer, Tony Danza," during the chorus instead of "Hold me closer, Tiny Dancer."
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The duo is also teaming up for a project called "Oh, It's Fantastic!", which calls on illustrators, animators and musicians to add imagery to a video they partially filmed in front of a live audience and a green screen. Artists will create images that go behind the green screen. For example, in one shot, they eat imaginary chocolate mousse, next to a moose made of chocolate, before getting swept away by a river of orange juice.
VISUAL ARTISTS + MUSICIANS: Work w/ us on our big musical number for our ep RE: #FANTASY w/ my friend @TonyDanza: http://t.co/Ym2sUQlZF0
— Joseph Gordon-Levitt (@hitRECordJoe) September 25, 2013
But the Levitt-Danza friendship is hardly new — it dates back nearly two decades when they worked together during 1994's Angels in the Outfield.
"I'm so proud of him and what he has done over the years and with this film," Danza told Mashable. "I've always felt like a father figure to him, but he's always been ambitious and mature. We used to rollerblade together while filming Angels in the Outfield and some days he'd want to just focus and pay attention to what was happening on set."
In Don Jon, Danza hurls obscenities at Gordon-Levitt's Don Jon character, who lets his love for Internet porn, particularly PornHub.com, get in the way of forming a real relationship.

"The film — and the porn plot line — really captures a modern issue in a really provactive way," Danza told Mashable. "Porn is all about access now. When I was younger, you would have to go buy a magazine from a deli where you had your two neighbors standing next to you with your Hustler behind your back."
Danza believes it's about time the topic of porn is brought to the mainstream, instead of sweeping it under the rug.
"It's something that is definitely happening and a lot of people don't talk about it," Danza said. "Scarlett has this theory that more women watch porn than men ."
Like so many films today, Don Jon is using social media to promote the film — a Twitter account managed by Gordon-Levitt (in the voice of his character) and a Don Jon Tumblr account.
Although Danza considers himself pretty tech savvy, he runs his own Twitter account but rarely goes on Facebook. He said one of the most challenging aspects about being a teacher was fighting for students' attention over technology. In 2010, Danza took on a long-term stint as a teacher in Philadelphia for his reality TV show Teach.
"I quickly learned kids can actually text while not looking at the phone and with their hand in their pocket," he said. "Some keep their earbuds in, and in one case, I had a student who was cheating by texting someone in the hallway for the answers. It's a complete distraction, but at the same time, it's very necessary, too."
Although Danza wasn't using tablets in the classroom, he believes tech is still an important part of the learning process. He embraced computers as much as possible.
"It's definitely different nowadays than when I was in school — and there are just so many distractions — but technology is doing so much to help students at the same time," he said.
Although Danza and Gordon-Levitt seem to be inseparable these days, he will star in his own new project "Honeymoon in Vegas," a play based on the movie of the same name, at the Paper Mill Playhouse in New Jersey.
"We hope it will go to Broadway," he said. "It's just really, really good."
Images: Mashable, Christina Ascani