Vista Print is offering Free Halloween tote bags, you only pay shipping costs (around $4). You could make this a sweet deal by combining with some of Vista Print's other Free offers. Here are a few of their current free offers:
10 Free Halloween Invitations
100 Free Postcards
250 Free Business Cards
Vista print always has items they are offering for free, but if you were looking for a Trick-or-Treating bag for your child, this could be a fun option!