Isn't It a Pity first saw the light of day on George Harrison's triple album All Things Must Pass in 1970, but it had been kicking around for a while before that. It had been apparently been vetoed by John Lennon during The Beatles' Get Back Sessions, and George may have put it forward as a Beatles track as early as 1966 for Revolver. If you're interested there's a lot more to the Isn't It a Pity story over at Wikipedia!

George recorded two versions for All Things Must Pass, which don't appear to be on YouTube... so here's a demo recorded during The Beatles' Get Back sessions

And here's George (although not sure of the source of this version)

Galaxie 500 covered the song on their second album On Fire:

The band didn't play it live because, according to this 1990 interview in Sounds, because it was "too hard":

I guess things get easier over time as Dean's been playing it a few times of late:

With Britta and Jonathan and Grasshopper of Mercury Rev:

With My Morning Jacket

And finally Dean & Britta struggling through it in Sweden

See all posts in the Originals series