A minor bridal emergency that happened to us recently that was a snap to rectify was that the bride forgot the ceremonial glass and pouch for the Jewish tradition of the breaking of the glass that happens at the end of the ceremony. She had purchased the set at a local store that matched her colors. Unfortunately it did not make it to the ceremony.
The quick fix: take a light bulb (makes for a great 'pop' when stepped on) or a wine glass and set it in the center of a cloth napkin. Bring the sides of the napkin around the glass and tie with preferably a ribbon. We wedding planner typically bring extra ribbon but if there is not a planner, ask the florist. If there is not a ribbon available, use a string, hair tie, garbage tie- hopefully white, or shoe string and voila! It looked great and no one new the difference.