Shawn Tribe of The New Liturgical Movement has put together a most informative post on the liturgical use of the so-called "righteous of the Old Testament" (mainly prophets) in the Eastern churches. Figures such as Abraham, Isaiah, and Elijah are commemorated with their own propers and icons, such as the one of Moses and the burning bush above. In the wake of Vatican II the western churches very laudably recovered the use of the Hebrew Scriptures in public worship, but could still stand, in my opinion, to incorporate some of these "ancestors in faith" into their liturgical calendars.

You can also click here for another Roman Catholic interpretation of typology.