Horizontal, black and white photos are custom framed in vertical mouldings with super long matboards. Just goes to show - don't let the orientation of the art determine where it will and won't fit. Anything's possible with custom framing!
If you're great at writing or art, you might be able to earn some money creating graphics and/or prose for greeting cards. This page has a huge list of 47 companies that are regularly seeking submissions from freelance writers and artists for the greeting