I was surprised to read the following quotes from someone quite unexpected:
"In the Lord's Supper the natural and essential body of Christ in which he suffered and is now seated in heaven at the right hand of God is not eaten naturally and literally but only spiritually."
"So then, when you come to the Lord's Supper to feed spiritually upon Christ, and when you thank the Lord for his great favour, for the redemption whereby you are delivered from despair, and for the pledge whereby you are assured of eternal salvation, when you join with your brethren in partaking of the bread and wine which are the tokens of the body of Christ, then in the true sense of the word you eat him sacramentally. You do inwardly that which you represent outwardly, your soul being strengthened by the faith which you attest in the tokens."
Yup, those quotes came from, you guessed it: Ulrich Zwingli!
(The quotes are from his Exposition of the Faith sent to King Francis of France. Thanks to Tom Nettles for the quotes.)