Fifty-six unreleased Jackson 5 master recordings auction online at Gotta Have It! tomorrow (September 19).
Which is the perfect time to unveil our list of 5 of the most amazing unreleased recordings.
Paul Fraser, founder of Paul Fraser Collectibles, commented: "Unreleased records are the holy grail for music memorabilia collectors.
"Finding a new recording by a legendary artist can add an entirely new dimension on their previous output.
"Whether it's an alternate version or an unheard song from their early years, there's something endlessly exciting about hearing that artist you love performing something you've never heard before.
"This incredible rarity and desirability ensures that values tend to start high."
5. The Rolling Stones
Little Boy Blue and the Blue Boys didn't take off -
Prior to fronting the biggest rock band on the planet, Mick Jagger and Keith Richards played in a group known as Little Boy Blue and the Blue Boys (the name a reference to their penchant for the blues).
The band recorded a selection of tracks in 1961, most of which were Chuck Berry and Elvis Presley covers.
Jagger paid £52,000 ($84,931) for the tape at Christie's London in 1995.
4. Jackson 5
Janet Jackson's underwear and patriarch Joe Jackson's business files are among the Jackson family lots auctioning tomorrow following the bankruptcy of a major collector.
Will the auction uncover some unknown gems? - i
Yet among the slightly grimy lots on offer are 56 master recordings from the Jackson 5 - the seminal soul group, formed in 1964.
Some of the marked tapes feature the band's biggest hits while others are unmarked, their contents a mystery.
3. Nick Drake
Nick Drake is one of the best loved British folk singers of all time, his distinctive voice and tragic story earning him a mythical status among his fans.
Nick Drake seldom performed for an audience - i
Famously he rarely performed live. Yet in July, a 1967 recording of him performing a selection of his songs was offered at Ted Owen Auctioneers with a valuation in excess of £250,000 ($429,756).
Ultimately, the sale fell through after an ownership row between the owner of the recording and Drake's former record label.
2. Bob Dylan
A set of 149 acetate recordings by Bob Dylan was recently discovered in an apartment in Greenwich Village, New York.
The building was used by the singer as a studio in the 1970s and the pressings forgotten when he left.
Dylan used the Greenwich Village apartment as a studio in the 70s - i
They include unheard alternate versions of songs from three albums he recorded in 1969 and 1970 (Nashville Skyline, Self Portrait and New Morning).
The finder contacted collector Jeff Gold, who commented in a post on music memorabilia site Recordmecca: "When I opened the boxes and took a quick look at the contents, I was blown away.
"They were indeed all by Dylan, all were in excellent condition, and many had handwritten notes on the sleeves.
"The sound on a carefully preserved acetate can be incredible - it's a first generation record made in real time directly from the master tape. And that was the case here."
Gold is selling a selection of the acetates on his website.
1. The Quarrymen
Only one tape of the Quarrymen, a skiffle group featuring three members of the Beatles, is known to exist.
John Lennon fronting the Quarrymen - image: Wikimedia Commons
It was recorded at a studio in Liverpool in 1958 and consists of two songs - Buddy Holly's That'll Be the Day and an original by Paul McCartney and George Harrison called In Spite of All the Danger.
After being shared around the band and their friends it was lost. The group eventually split up and McCartney, Harrison and Lennon went on to form the Beatles.
The rest is history.
John Lowe, a member of the Quarrymen, found the recording in the early 1980s and offered it to McCartney - who paid him an unrecorded sum.