Most of the tributes that will pour in on her death will focus on her well-known songs (the BBC overnight was endlessly rehashing extracts of I Say A Little Prayer, Respect, and Natural Woman). Few will demonstrate why they think she was unique. Here's a good example: Call Me.
Sadly, it's not her best performance of this song to be captured on tape. That one was available online in 2011, but has probably been removed for copyright reasons. It was a television performance circa 1971; the audience was seated around tables - and it's not the one on the Tom Jones program, which you can still find online.
For me, her other most notable high point was the 1973 single Angel. Also worthwhile amongst many others is her recording of The Band's The Weight, which is also quite a spiritual song.