Noel Gallagher & The High Flying Birds: He's already declared himself a bit miffed not to have been asked to play in the first place, so perhaps this is the Eavis' time to right those wrongs. He'd have to reschedule his gig in Switzerland though.
Coldplay: They've played a few times before and gone down as well as Coldplay ever go down (i.e. solidly, but with the inevitable detractors) so they'd be a safe pair of hands. They've also decalred their next album will be their last, so could this be the best way to launch it with one final Glato slot? Plus, their schedule is wide open.
Taylor Swift: We can only imagine the hand-wringing and cries of "but what about REAL MUSIC?!?!" that this would provoke from those who signed that Kanye West petition - and for this reason, as well as the fact that it would be really, really fun, we hope it's Swifty. Plus. she'll be in the country at that time so she has no excuse.
Muse: They'd be severely disappointing their Swedish fans if they took the mantle - they're due to perform in Norrkoping that night - but it would probably be worth it. Especially after they destroyed Download Festival last weekend.
Blur: They went down a storm when they headlined Isle Of Wight Festival this past weekend, and, after a Hyde Park gig on 20 June, they're free for a month. A definite possibility - and they're Glasto regulars.
Queen & Adam Lambert: We're not quite sure how a Venn Diagram of Queen fans and Foo Fighters fans would look, but we're assuming there must be at least some overlap. They'd be sure to put on a spectacular, theatrical show, and would perhaps be welcomed even more warmly than the Foo Fighters would have been.
The Libertines: Originally rumoured for the festival, could they show up and bring Albion and their long-awaited third album to the good fields of Glasto? They have that night free, but have to be in Russia the next night. Stranger things have happened.
Prince: Because come on - it has to happen eventually...
Florence + The Machine: She's already on the bill, so in many ways this would be a bit of a disappointment - except that if she headlined, her set would surely be more big, more blue, more beautiful. Sadly, she started the trend for breaking legs and is currently not particularly mobile.
Stone Roses: They're one of the bookies' favourites, and they aren't doing anything on that date, but for some reason this just doesn't seem likely to us.
AC/DC: They've got a series of UK dates scheduled for just after Glastonbury, so perhaps this could be a very, very intense warm-up shows for those?
Radiohead: It's been a little while since Radiohead have played live, and they don't have any dates lined up - so in one way, that makes this something of a long shot. On the other hand though - what a comeback.