I used to think that my photos needed color to be compelling, but a good black-and-white image can be very powerful. Of course, producing a monochrome image from a color one is not as simple as removing the color information.
Talented photographers like the late Ansel Adams, who worked primarily in black and white, often shot with colored filters to highlight certain aspects of a subject, and then spent hours in the darkroom getting the tonality just right.
Today, there's a Mac app called Tonality. It's US$24.99 (on sale for $17.99 through the weekend) at the Mac App Store, and it offers great control over the final look of your black-and-white image. Yes, many of these tools are available in Photoshop and Lightroom, but this app is quicker and easier to use.
It features more than 150 pre-sets to get you started, but you can easily create your own looks. The app even supports digital color filters, so you can get very selective about how skies and other things in your image translate to black and white. For example, A red filter, used so frequently by Ansel Adams, darkens a light sky while letting the tones of the landscape pass mostly unchanged. Tonality gives you the freedom to experiment and create some really stunning photos.