Monday of Holy Week

(From The Pieta) Our Lord told St. Gertrude that the following prayer would release 1000 souls from Purgatory each time it is said. The prayer was extended to include living sinners as well:

Eternal Father, I offer Thee the most precious blood of Thy Divine Son Jesus, in union with the Masses said throughout the world today, for all the Holy Souls in Purgatory, for sinners everywhere, for sinners in the universal church, those in my own home and within my family. Amen.

This would be a good one to say whenever you are stuck in traffic, or otherwise waiting around for something to begin, for example if you arrive early for Mass or other appointments.