Paper treat bags are just the right size to serve as festive envelopes for 5-by-7-inch holiday photo cards printed on heavyweight photo paper. Use mailing labels to make addressing easy, and then add postage. They're cheaper than envelopes and come in a range of colors and patterns.
Shipping labels, by Martha Stewart Home Office With Avery, in Red Classic Border, $4 for a pack of 18, staples.com. Party favor bag, in Mod Circle Red, $6 for 24, thesugardiva.com. White Kraft Chevron paper bag, medium, $7 for 25, paperpresentation.com. Epson Premium Presentation paper, matte finish, $15, staples.com.