St. Faustina and the Divine Mercy Chaplet
Saint Maria Faustina Kowalska was a humble instrument of God's mercy. She was a virtually uneducated nun with the Congregation of Sisters of Our Lady of Mercy. With only three years of simple education, Sister Faustina was often appointed the most menial tasks of gardening and kitchen work in the convent. However by God's grace, she received great revelations from Jesus. This revelations were recorded in Diary of Saint Maria Faustina Kowlaska. The message of God's mercy toward us all is the leitmotif of all of her writings.
In contemporary terms, St. Faustina's principal endowment to the church is her Divine Mercy Chaplet.
The Vatican has recently announced a Plenary Indulgence for the Divine Mercy Chaplet. If this is a devotion that is close to your heart, or one about which you are a complete neophyte - consider incorporating this into your prayer-life.