The Qur'an says that Allah is the God of the Jewish patriarch Abraham and of Jesus. The New Testament states that the Christian God is also the God of Abraham, and in it St. Paul maintains that he is both a Jew and a Christian (Acts 22). Therefore, I think Jews, Christians and Muslims might pray together as practitioners of the three Abrahamic religions. I offer the following experiment in that direction. I intend no offense. I hope to promote dialogue, not syncretism.
This prayer is for reading aloud by three voices, representing the three faith-communities who claim to be Children of Abraham — Jews, Christians, and Muslims. "S" indicates the the Shema, the prayer of Israel (Deuteronomy 6:4-9), "F" indicates al-Fatihah, the Opening chapter of the Qur'an, and "L" indicates the Lord's Prayer from the Gospel according to Matthew (6:9-13).