Today's airwaves might be dominated by entertainment shows like Dancing With the Stars and America's Got Talent. But, back in 1962, a young woman sang a song which still outshines them all.
Forty-eight years ago this week, Marilyn Monroe famously sang "Happy Birthday, Mr President" for John F Kennedy, and her song still captivates people today as much as it did back then.
But, for some people, Monroe's legendary performance at Madison Square Garden isn't just something that touched hearts - it is also a viable place to invest their cash.
Memorabilia from Monroe's life and career has consistently sold for enormous sums at public auctions in recent years, and values are continuing to rise.
 Marilyn Monroe's memorabilia has consistently sold for enormous sums of money at public auction |
Notable sales include the auctioning of the dress worn by Monroe at the "Happy Birthday" concert. Specially designed and made for the occasion by John Louis, it sold for $1.26 million in 1999.
The dress is now listed in the Guinness Book of Records as the most expensive piece of clothing ever sold, and is estimated to be worth even more today.
Leading memorabilia dealers like Julien's Auctions in the US regularly pass Monroe memorabilia over their auction block, alongside fellow icons like Elvis Presley.
"About a year ago we had a Monroe umbrella that we estimated at $10,000-20,000," says company head Darren Julien. "It went for $49,000."
Other big sales held in recent years include Monroe's make-up kit for $266,500, auctioned in 1999, and an umbrella from a famous 1949 photoshoot which brought $42,000.
But, while it is evident that these collectibles sell for huge amounts, what exactly is it that makes them so appealing to investors?
One answer can be found in the sale of Marilyn Monroe's bathrobe, which auctioned at Julien's in July 2009 for $120,000.
Considering that the same bathrobe was bought for $6,000 ten years previously - equalling an annual value appreciation of 35% - the appeal of memorabilia to investors becomes clearer.
Items that were very personal to the celebrity are likely to fetch higher prices at auction, says Adrian Roose, director at Paul Fraser Collectibles in Bristol.
 Monroe's bathrobe, an example of a personal item, sold for $120,000 at auction |
"Perhaps the most bizarre sale that we've seen involved Polaroid photos that Marilyn took of her pet dog," says Mr Roose.
"This isn't a joke - photos of Marilyn's dog sold for almost $250,000 in New York a few years ago."
Another collection of Monroe photographs - this time of Marilyn rather than her dog - sold for $146,000. They were shot for Vogue magazine in the year that she died.
Those particular photographs weren't signed. But autographed images of Monroe, if authentic and sufficiently rare, can sell for up to $13,000.
According to experts, the value of a piece of memorabilia, especially autographs, depends on their rarity.
For instance, despite his recent problems Tiger Woods is still one of the world's most valuable signatures because he rarely signs them.
And Mike Heffner at Lelands auctioneers in New York believes that Woods' recent troubles could boost rather than reduce the prices of his memorabilia.
"I'd say he'll be more elusive when it comes to signing, which, in turn, will make the value even greater," says Mr Heffner.
Some Monroe autographs are rarer than others. For this reason, they can be bought for a range of prices.
In the actress's heyday, movie studios often insisted that their stars send autographed responses to fan mail. These more common Monroe signatures are relatively cheap on today's market.
On the other hand, rare and one-of-a-kind autographs - like signatures on important legal documents - are usually worth considerably more.
Limited supply in the face of growing demand is a big advantage that the memorabilia of deceased celebrities can hold for investors.
 The Some Like it Hot star's lingerie is for sale to collectors priced $15,675 |
William Shakespeare's autograph, for example, is the most valuable in the world partly because only six are thought to exist - and they will never cease to be sought after by collectors.
The impact of death on memorabilia values was further underlined following Michael Jackson's fatal drugs overdose in July, 2009.
During the singer's lifetime, Andy Warhol's pop art portraits of Jackson had underperformed at auction. One sold for $278,000 in May 2009, while another was left without a buyer.
However, in the month following the King of Pop's death last year, a Jackson print by Warhol sold for a massive $1 million in New York.
With memorabilia, being dead can enhance rather than hinder a celebrity's earning power - to the extent that Forbes magazine publishes an annual Dead Celebrity Rich List.
Marilyn Monroe is at number nine on Forbes' list, and is currently the only female listed. Her posthumous earnings last year totalled $6m.
And it also helps that Monroe lead such a colourful life prior to her death.
Key moments, such as the her performance of "Happy Birthday" for JFK, are all the more fascinating because of the couple's alleged affair.
 Rare and authentic Monroe signatures can bring values up to $13,000 |
Such interest may have stoked the interest of bidders competing for a gold Rolex watch, believed to have been gifted by Monroe to JFK in 1962.
Inscribed "Jack, with love as always from Marilyn May 29th 1962," the Rolex sold for $120,000 at Alexander Auctions in 2005.
A popular tale is that Kennedy told a White House aide to "get rid" of the watch after ending his illicit affair with Monroe.
Elsewhere, more unique items to appear on the collectibles markets include the hair of deceased celebrities.
A single strand of Elvis Presley's hair was sold for $1,750 by auctioneer Henry Aldridge & Son in Wiltshire, UK, last year.
The strand had been kept by Homer Gill Gilleland, Elvis' barber, who toured with The King for more than 20 years.
Memorabilia dealers with historic hair in their cupboards include Paul Fraser Collectibles, which holds about 1,000 strands cut from Monroe's head on the day she sang for JFK.
"Our company deals in unique items with impeccable provenance and an interesting story," says Adrian Roose.
"So Marilyn's blonde locks cut by her personal hairdresser on the afternoon of the "Happy Birthday, Mr President" performance is about as good as it gets."
The hair is accompanied by a previously unseen photograph of Marilyn on the night of the performance, on which she has applied a lipstick kiss on the reverse.
Asked how important a piece this is, Mr Roose replied: "Given the personal nature of the hair and the lipstick photo, it has to be on a par with the $1.26 million dress."
In recent years, locks from the heads of other historic icons like Elvis Presley and Charles Dickens have sold to collectors for thousands of pounds on the private market.
