The only aspect of Sam's character that might exceed his brutal honesty is...

Sam, the unlikely star of the show, isn't really trying to be funny. Until last week, Sam had no idea his youngest son had been broadcasting his anecdotes for the world to read. But you could write a book about Sam. Indeed, Justin has already signed with an agent and is considering offers from book publishers.

Justin started Twittering his dad's musings on Aug. 3. In less than a month, the page has gotten shout-outs from "The Daily Show's" Rob Corddry , a popular San Francisco blog called Laughing Squid and "Forgetting Sarah Marshall" star Kristen Bell . Corddry told his nearly 1 million followers it's "the best thing ever." Bell urges others to read it "unless you're allergic to laughing hysterically."

The site, which we'll prudishly call Stuff My Dad Says , contains droll, irreverent fragments of conversation, observation and, in many cases, expletives stemming from the retired 73-year-old's frustrations with his three sons, the mysteries of technology, and actress Kate Beckinsale . "Who is this woman?" he asks secondhand in one tweet. "Kate Beckinsale? Well, you can tell Kate Beckinsale she sucks."

We should preface this story with a disclaimer: Justin and his dad use profane language. A lot of it. In fact, the very name of the Twitter page Justin runs contains a word synonymous with human waste that is unsuitable for a family publication. The tweets themselves contain still more naughty language. So, click at your own risk.

Once a day, Halpern, 28, posts a memorable quote that his dad, Samuel, had said the day before. More than 200,000 users subscribe to get their daily dose of Sam.

In Justin Halpern 's case, moving from Los Angeles to his parents' house in San Diego planted the seeds for a Twitter page that's quickly growing into an Internet phenomenon, attracting offers from literary agents and book publishers.

Having to move back home at the age of 28 almost universally signals defeat. Images of an unemployed, not-so-well-adjusted George Costanza character from "Seinfeld" might spring to mind.

Justin Halpern, right, and his father, Samuel Halpern, third from the right, attending the World Baseball Classic with Justin's friend Brad Lamers, sitting in the middle. Credit: Patrick Schumacker / For The Times

... his insistence on absolute privacy. Before retiring, Sam worked in nuclear medicine for the University of California, San Diego. As you might imagine with a state-funded job that requires classified research, Sam kept many aspects of his life close to his chest.

Despite data that suggest that Facebook is popular among older people, you will almost certainly never see Sam on a social network. He keeps a separate computer from his wife on the other side of the house that isn't connected to the Internet.

"I wasn't worried it was going to get back to him," Justin said about Sam discovering the site. "He doesn't go on the Internet. It was like I was writing a newspaper on Mars."

In all aspects, Sam takes his privacy very seriously -- a detail not lost on his family. "You do not screw with my dad when he's in the bathroom," Justin said. "My brothers and I know this for sure. You never knock on the bathroom door when my dad is in."

Growing up, Justin and his two brothers were pretty scared of Sam. Heck, they're still scared of him. After telling Justin's brother, Dan, about Stuff My Dad Says, Justin remembered Dan laughing hysterically to the point of tears. Then, Dan's tone changed. "Dude, you can't tell Dad," Justin recalled his brother advising him.

So, the fact that Justin was getting offers for book deals and that the number of subscribers to the page had ballooned to about the equivalent of Glendale's population gave him reason enough to fear his father's reaction when he finally broke the news.

One night about a week ago, after walking a few miles around their neighborhood in San Diego to organize his thoughts, Justin gathered up his courage and dropped the bomb.

"I told him, 'OK, there's this site called Twitter.' And he was like, 'I know Twitter.' And then he was like, 'Now, do you have to go onto the Internet to access Twitter?' "

After providing a basic overview of the project, Justin prepared for the fallout. "I should have seen it coming," Justin said. "He gave the most perfect response. He laughed for, like, 10 seconds, and then he goes, 'I can't find my cellphone. Can you call it?'"

Somehow, disaster was averted.

Justin's other major concern leading up to the confession -- aside from his dad being furious with him -- was whether the awareness would change the things Sam said and how he acted. Fortunately, fame hasn't gone to his head. "He really doesn't give a crap," Justin said, but "I think he doesn't fully understand it."

Sam did have one stipulation after hearing about the experiment. "Keep the money from whatever you get. I have my own money," Justin recalled his dad saying. "I just don't want to do any interviews."

He reinforced that last week when The Times requested Justin pitch the interview idea again to his father, who is apparently a longtime reader of the newspaper. "'The L.A. Times wants to interv --' 'No,' " Justin recapped in an e-mail.

"He hates attention," Justin said about his dad. And he has reason to. Sam had a long career in a highly secretive medical field and fought in a very unpopular war. The son of a Southern sharecropper, he would help around the farm as a child, tending to the tobacco fields. Not exactly a glamorous lifestyle.

Sam inherited a unique trait from Justin's grandfather. "I probably saw him more often without clothes than I saw him with clothes on," Justin said about growing up with his dad. "I think they would just get done with the farming, and they would be really tired. And they would just strip down and walk around naked."

"It would be awkward because friends would be coming over, and I would have to be like, 'You know, you have to put clothes on,' " Justin reminisced. His friends have long loved Sam. They, too, have seen the grizzled man in the buff.

Justin has an almost endless number of hysterical stories about his dad. There was the time Sam coached Justin's little league team and got so frustrated with the players that he quit the gig on the spot, leaving a 9-year-old Justin to walk a few miles home.

"Even at 9, I knew this was going to end terribly," Justin said. "It was just me walking home, and I saw him driving. And he pulls up next to me and says, 'Aw, I forgot to pick you up, didn't I?' ... 'I'm not coaching that [expletive deleted] team anymore.' "

And then there was the time Justin filled Sam's Alfa Romeo Spider convertible with water. Or the time Sam had a bad day and declared, "I'll wear clothes if I want to wear clothes, and I won't wear clothes if I don't want to wear clothes," Justin recited. "And the fact that your friends are coming over soon is inconsequential."

Justin had been scribbling down his dad's rants and quips in a notebook since childhood. In the last year or so, he began updating his Google Talk instant messenger status with quotes to laugh about later with friends who know his dad. One of them, who had become quite adept at Twitter, suggested Justin use the service to actually preserve the fragments. (Google Talk statuses are not archived.)

For a week or so after he created the account at the beginning of August, Stuff My Dad Says had five followers -- all friends of Justin. His buddy, who runs a fairly popular Fake Michael Bay Twitter page ("EXPLOSIONS!"), asked Justin if he could give him a shout-out on the weekly #followfriday ritual, where Twitterers suggest friends to their followers.

"Nobody knows my dad, so it's not going to make any sense," Justin recalled telling him. (Justin's mom had the same reaction when he told her about the site.) Regardless, on Aug. 14, the tweet went out, and Stuff My Dad Says exploded. He began picking up a few hundred followers a day. Now, it's a few hundred per minute.

Justin places no ads by which to earn revenue on the page. Twitter doesn't have a platform for monetizing a feed -- not that Justin necessarily cares to.

"The reactions have been all really positive," Justin said. "And people telling me I'm a loser, which I'm fine with."

Contrary to the "28-year-old guy living with his parents" stereotype, Justin is, in fact, employed. (He says he moved back to San Diego to get away from the big city life in L.A.) He recently left his job writing for the humor website he founded, called Holy Taco, along with his co-founder, Cory Jones, to write for "Maxim."

"I wish maybe I wasn't living at home," Justin said during a phone interview. "But if you had to live at home when you were 28, this is a good situation. I really like my mom; I love my dad; I love my dog." At this point, Sam can be heard in the background quipping about how he loves the dog, too.

Sam may have wanted his son to be a professional baseball player after bonding for many years over the sport. (A recent Stuff My Dad Says tweet about the pair watching the Little League World Series read, "These kids are all fat. I remember when you were in little league.... You were fat.") But he fully supported Justin's pursuit of becoming a writer.

"He's a really good dad," Justin said. "He just doesn't let you get away with anything."

Corrected, 5:20 p.m.: The original version said Samuel Halpern worked at the University of California, Santa Barbara. In fact, it was at the University of California, San Diego.

-- Mark Milian

Follow my commentary on technology and social media on Twitter @markmilian.