Joan Rivers could barely keep a straight face when she got up close and personal with music mogul 50 Cent in NYC on Tuesday.

It what could be the makings of the new "Odd Couple," the 78-year-old comedian even got a peck on the ear from Fiddy at a shoot for his Street King energy drink.

Forget can we tawk ... can she rap?

Joan Rivers narrowly escaped what could have been a fatal mishap this morning -- and one that would have lived in infamy -- her manhole exploded in flames.

Joan and her daughter Melissa left the 78-year-old's NYC apartment this AM to do a segment for "Good Morning America" -- to promote their reality show, "Joan & Melissa: Joan Knows Best?"

As their car pulled away from the curb, a manhole cover -- just feet away -- blew sky high, with flames shooting in the air.

We called Joan for comment.  She said, "The only thing I know about manholes is what my gay porn star friends tell me."

Dating a porn king has brought Melissa Rivers into the adult film universe -- and now one company wants her to take it a step further, and make an adult tape of her own!

As TMZ first reported, Rivers is now dating Steven Hirsch the head man at Vivid Entertainment ... a company famous for selling celebrity sex tapes.

But another adult company, PornHub.com, has fired off a letter to Rivers to see if she and her new BF would be interested in filming a tape for them. The company believes it would be the first sex tape to feature "a sexy Jewish American Princess."

Some barriers are never meant to be broken.

Joan Rivers couldn't be happier her daughter is dating the god of sex tapes Steve Hirsch -- telling TMZ Live, Melissa Rivers and her new XXX man are a perfect fit ... in more ways than one.

Joan tells us, not only is Steve crazy about Melissa -- "He makes a great living ... and he's Jewish."

But Melissa -- who hooked up with Steve through a friend -- isn't the only one reaping the benefits of her new relationship ... Joan adds, "I'm 78 years old and now I get a discount on lubricant."

TMZ broke the story -- Melissa and the Vivid honcho have been dating for a couple weeks now -- and sources tell us ... "The relationship is going great."

Going in a, um ... different direction this year, TMZ has learned the folks at GoDaddy.co are using Joan Rivers as their Super Bowl spokeswoman.


Look for Joan to be featured in an ad at some point during today's big game.

That's old school.

Joan Rivers has been canceled from a scheduled appearance on FOX & Friends -- she says it's all over a comment she made to TMZ blasting Sarah Palin ... but FOX denies that's the reason.


This weekend, Rivers said she partially blamed the Arizona shootings on Palin ... and then referred to Sarah as "stupid and a threat."

Rivers was scheduled to appear with daughter Melissa tomorrow on the show to promote her new show, "Joan & Melissa: Joan Knows Best?"  River's rep tells us a producer called to say they gave her the chop because of Joan's comments.

But moments ago FOX responded ... they say the show was overbooked and the producer "mistakenly" canceled Joan's appearance instead of rescheduling it.

FOX insists it has nothing to do with Joan's comments.

Sarah Palin deserves criticism -- and BLAME -- for the horrifying shooting in Tucson, AZ ... this according to Joan Rivers.


Joan was at the Critic's Choice Awards party in Hollywood this weekend when things turned political -- and Joan exclaimed ... "This woman is just stupid and a threat."

So we gotta ask...
 

Take a magical trip through time and watch Joan Rivers' natural beauty progress from the early '80s into the "Piece of Work" she is today!

Joan Rivers is being sued by a bitter ex-manager -- who claims he was never compensated for resurrecting Joan's "dormant career" ... but it's clear this lawsuit is as much about hurt feelings as lost money. 


The guy going after Rivers is Billy Sammeth -- Joan's longtime "personal manager" -- who claims he "took [Joan's] dormant career" ... and found a way to get her more work and more money ... only to be stiffed out of $179k and humiliated in a recent documentary about Joan's life.

In the docs, Sammeth claims he never got his 10% cut from several paydays Joan received -- including a $200,000 check Joan received from winning "Celebrity Apprentice."

Sammeth also claims Joan and the people behind the documentary "Joan Rivers: A Piece of Work" -- defamed him by making him appear to be a "disappeared" manager.

Sammeth is suing both Joan and the production company for at least $2.2 million. 

UPDATE: A rep for Joan tells us the comedian is, "confident that the judicial system will dispose of Mr. Sammeth's lawsuit in the appropriate manner."

Funny ladies Kathy Griffin and Joan Rivers worked it out at the same event in NYC on Monday.



Question is ...