More than 20 billion paper catalogs are mailed every year in the United States. Many often go unread, unrecycled and straight from the mailbox to the trash can. If there are some catalogs you enjoy receiving and browsing, think digital instead. Many major retailers are now offering free downloadable versions of their catalogs to tablet devices like the iPad. You can subscribe to the catalogs just like magazines. When new items are available, it will be updated automatically and ready to browse. It's paperless and one more way technology is helping to green our lives.