Projecting a professional image is crucial to success in today's competitive market. Sometimes the old answering machine with the scratchy message saying, "Please leave a message after the beep," just doesn't cut it. Bogen Communications has introduced Friday, a digital voice-mail system designed specifically for small businesses. Friday features eight voice-mailboxes — four individual ones, three announcement-only boxes, and a secure dataport that connects to a desktop computer and can also be used as an automatic fax machine switch. Any of the individual boxes can forward calls to a remote phone or a pager. You can even plug in your tape deck and play your own on-hold music. The Friday- 1000, which operates on a single phone line, sells for about