The Duck Pillow is a pillow obtainable in the store/pillows page in PFS. The pillow is a yellow ducked skinned with yellow feathers being particles emitted.
The duck song is as follows:
(Bum bum bum, ba-dum ba-dum)
A duck walked up to a lemonade stand
And he said to the man, running the stand
"Hey! (Bum bum bum) Got any grapes?"
The man said
"No, but if you don't go away I'll make you into a pillow"
And thus the Duck Pillow was born.
Well in my eyes it was.