Friday penance. Every Friday of the year is penitential, not only in Lent.
Fasting. What the Church actually requires, and what it is for.
Ember days. Four sets of three days that mark the turn of the seasons.
First Fridays and First Saturdays. Two monthly devotions with conditions attached.
Novenas. Nine days of prayer for one intention.
The Angelus. Three pauses a day at six, noon, and six.