Think outside the box when planning your do-it-yourself projects with stone. Instead of using traditional flagstone for a mortared patio or walkway, consider thin stone (two or three inches thick and generally flat in appearance) for a more informal natural look. Thin stone is also a good alternative candidate to replace traditional building stone (three to nine inches thick and generally rectangular) for smaller garden wall or low retaining wall projects. Consider thin stone stacked to create a natural permanent planter or rustic mailbox column.   Another option for stacked walls or edging instead of building stone is Ashlar stone (split or cut to be flat on two sides and uniform in height or length) for a more formal look.     Dimensional stone (custom-cut to specific shapes and sizes) such as bluestone, limestone, sandstone and slate offer infinite possibilities limited only by your imagination - as wall caps, tread material, coping around walkways or pool decks. Stone in any hardscape application gets more beautiful with age and is almost always low maintenance. Let your creativity go wild when you consider your stone hardscaping options.