Mac users interested in Snail mail by nixanz generally download:
Work with the Address Book database in Mac OS X 10.2 or higher by opening and managing single envelopes based on its entries. The utility works with individual files or in a batch mode and provides detailed descriptions of current address parameters. Printing options are available.
Labels & Addresses is a simple graphic utility that enables you to design and print envelopes, business cards, mailing labels, barcodes, price tags, and many others. The program allows you to import images from your local directories, choose between dozens of quality project templates, and export the final products to multiple file formats.