I had a friend of mine help me do a cover of Edie Brickell's "Love Like We Do" which was a very nice double meaning kind of experience for me. It was back when I was newly poly and when I was newly emboldened to perform in front of people. I sang it to someone special and it reminds me of her, but it also makes me feel very good about my way of being.
Specifically the segment that says "A situation for the lucky few who know love like we do".
Along those same lines, the same goes for "Just Because" by Anita Baker. Specifically "When I think about how much I'm loving you, no limitations, no set of regimented rules" and "It's amazing loving you, I'm doing things I never thought I'd do." and "I don't know, there ain't no explaination for why I'm sharing love at last this way"
Both of those songs really do it for me.