Pink Floyd - the case for: Roger Waters and David Gilmour are still very much active, with David Gilmour set to return to Pompeii this year 45 years after the band recorded their iconic concert film there, while Waters' The Wall tour is the highest-grossing of all time by a solo artist.
Pink Floyd - the case against: Both Syd Barrett and Rick Wright have died in the last decade, and in an interview with The Telegraph, David Gilmour said, "I just don't wnat to do it with the remains of those guys any more. Roger and I don't particularly get along... It would be impossible for us to work together."
The Smiths - the case for: Morrissey's just about had enough of his own solo tour, and Johnny Marr is still heavily involved in the music scene. Plus, next year marks the 30th anniversary of their split - which would be a perfect time to reunite.
The Smiths - the case against: "I don't know a single person who wants a Smiths reunion," Morrissey told Billboard recently, proving that he hasn't interacted with many people. It seems he's still not keen though, and given that the band turned down $50 million to reform back in 2009, it looks like nothing is going to bring them back together.
Destiny's Child - the case for: Their back catalogue has only grown in popularity over the past decade, and former manager (and Beyonce's dad) Matthew Knowles recently said he's "extremely hopeful" that the trio will reunite.
Destiny's Child - the case against: First of all, Beyonce isn't exactly on good terms with her dad, so his hope is all but meaningless. Secondly, Beyonce's pretty busy being the biggest popstar on the planet.
Led Zeppelin - the case for: It goes without saying that there's a huge appetite for a Led Zeppelin reunion, and at the end of last year, Jason Bonham made headlines when he said, "In my heart of hearts, I do believe we will play again."
Led Zeppelin - the case against: Jason Bonham isn't really a key member though - he only replaced his father John Bonham for a handful of gigs. Just a few months before Bonham's comments, Jimmy Page said, "I can't foresee doing it again, because we all have to agree and agree for the right reasons."
Oasis - the case for: Brothers Liam and Noel Gallagher have made peace with each other now - or as close to peace as they're ever likely to get - and the popularity of The Libertines' and The Stone Roses' reunions shows that their fanbase is still as eager as ever.
Oasis - the case against: Both Liam and Noel have repeatedly denied rumours that they're joining forces again. Last year, Noel told Chris Moyles, "Probably not in the very near future. One should never say never though, when someone's waving a cheque for a quarter of a billion." In other words, this one's all-but guaranteed - you just might have to wait a decade or two.
Fugees - the case for: The '90s hip hop group are just as important and relevant now as they were two decades ago, despite only releasing two albums, and Lauryn Hill is out of prison and back in the spotlight. Back in 2014, Wyclef Jean said, "I'm all for that, 100 percent."
Fugees - the case against: With a brilliant solo album under her belt, and a career revival in full swing, why would Lauryn Hill want to reunite with the band that she once described as "a conspiracy to control, to manipulate and to encourage dependence"?
ABBA - the case for: With the help of the Mamma Mia musical, ABBA's music is now popular with a whole new generation of pop fans, and even tribute act Bjorn Again frequently enjoy a high billing at festivals.
ABBA - the case against: They're still all divorced and estranged, and when they reunited on stage for the first time in 30 years back in January, it was merely to introduce a new restaurant, and they refused to even be photographed together on the red carpet.
The Kinks - the case for: Last year, Ray and Dave Davies shared a stage together for the first time in nearly 20 years, in Islington Assembly Hall in north London.
The Kinks - the case against: After rumours that they were set to reform for this year's Glastonbury, 20 years after their acrimonious split, turned out not to be true (unless Emily Eavis has a surprise up her sleeve), it seems unlikely that the pair are going to reunite.
Spice Girls - the case for: Mel B has been telling the press that it's going to happen for several months now, as the band head towards the 20th anniversary of their debut single, 'Wannabe'. "We're doing something at some point with, hopefully, all of us," she insisted.
Spice Girls - the case against: It may well happen, but Victoria Beckham won't be involved. A rep for the former Posh Spice said, "Victoria has been very respectful about the fabulous time they had together in the past, however her focus is now very much her family and fashion business."
Bikini Kill - the case for: It's been a big few years for the re-emergence of Riot Grrrl - both in terms of reformations (Sleater-Kinney, Babes In Toyland, etc), and up-and-coming artists influenced by the movement. So what better time for the band at the forefront of the movement to reunite?
Bikini Kill - the case against: Last year, they re-released their 1991 demo, complete with three unreleased tracks. One suspects that if they were planning on reuniting for a tour, that would have been the time to do it.
Genesis - the case for: Phil Collins recently told The Telegraph, "I'd love to do it," adding "The voice is alright, that's the main thing."
Genesis - the case against: He then added, "It puts a bit of a kibosh on it if I can't play the drums" - and whatever happens, founding member Peter Gabriel is unlikely to be involved.