It's by the High Kings, of course, and I dare you to listen to it just once. I may or may not have listened to it at least 20 times over the past two days...
'Phil the Fluther's Ball' (or Fluter, depending on your source) is sadly not a song included on any of their albums, which would explain why I had somehow overlooked it until now. I must have heard it at least once before, because they perform it during their original recorded concert that is based on their first album that came out way back in 2007. But how I was not immediately captivated by this foot-tapping song, I'll never know.
To my great excitement, Brian Dunphy (one of the High Kings, if you didn't know already) did record this song on a solo album Timeless, and it sounds almost identical. It is missing the magical blend that the four of them have together, but it is still a cracking song that is hard to stop listening to!
And now, for your listening pleasure, I present the High Kings performing 'Phil the Fluther's Ball':