What are Hostess Gifts?
A hostess gift is what you send to the hostess of the swap in addition to the cards or items to be swapped out.
You can send a gift as a token of appreciation if you desire, it is not required but is a nice gesture and a small gift of appreciation to the hostess for organizing and running a swap which takes much time, effort and sometimes headaches.
A hostess gift can be anything you can fit into the envelope without costing too much more to mail it to the hostess.
You can check the RAK ideas list for more ideas.