Travel snaps can do more than just record your trip: they can also record your impressions.
Select the "Monochrome" Picture Control to take photos in shades of sepia or other monochrome tints.
You can also use image retouch to edit pictures after the fact, creating a variety effects from a single photo. The "Monochrome" option, for example, can change a photograph completely. The trick is to imagine how the photo will look in monochrome when you take the original image. This will help in producing monochrome images that make effective use of light and dark.