My mother always liked this song (by Lee Hayes from The Weavers:

If I should die before I wake,
All my bones and sinew take.
Put me on the compost pile
To decompose me for a while
Sun, worms, water shall have their way
Returning me to common clay.
When radishes and corn you munch
You may be having me for lunch!

And then, excrete me with a grin,
chortling: "There goes Lee agin."

(We didn't actually sing it at her memorial, but we did scatter a good bit of her ashes over the compost pile).