I've seen the custom quoted in many siddurim to recite Psalm 130 (שיר המעלות ממעמקים), with the Ark open, between ישתבח and ברכו during עשרת ימי תשובה. Why this Psalm? What special relevance does it ...
If one does the Minhag of Kapparos on money, how much money should be used for each person? (Sources.)