Feeding systems for documents or other sheet materials include: (a) an inlet; (b) an outlet; (c) a feed path extending between the inlet and outlet; and (d) a feed system that moves materials along the feed path. The systems further may include: (e) a bidirectional feed path extending from the feed path; (f) a supply system that moves materials to the feed path; (g) a bidirectional drive system that moves materials along the bidirectional feed path; and/or (h) a bidirectional feed path access control system. Drive systems may be provided for driving the feed system and at least one of the supply system, the bidirectional drive system, and/or the access control system such that operation of the feed system is independent of operation of the other systems and/or such that a single motor may be used to drive any or all of the systems.