1. 'Nuclear Seasons'

This should've been number one for at least three weeks in every country in the world but it somehow wasn't and, although we're not ones to hold grudges, we're not quite over it. Before anyone really knew who Charli XCX was, if you signed up for her mailing list you got a free download of this track. Which is incredible when you come to think of it because 'Nuclear Seasons' is, undeniably, her best song and she nevertheless gave it away for free. How generous is that? Oh wait, that may explain why it wasn't number one for three weeks in every country in the world. Either way, it still sounds as fresh as it did when it first came out in 2011. Also, how great is the lyric: ""When you go please don't leave your love in the sun /my heart would melt away"? Very.

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