Organise who brings what for a Potluck or Bring A Plate Party. Define some foods, define who can access it and email your friends. They will be able to pick an item each.
Organise what gifts the bride and groom would like to receive. Define a list of gifts, define a list of attendees and email them. They will be able to come here and mark off what they are going to get for the bride and groom..