Asbestos siding, also known as cement asbestos siding or slate siding, is only found on older homes and isn't manufactured anymore. Though it's just finely ground asbestos particles mixed with cement, since it's mixed with the cement, it can't be breathed and isn't a health threat. To make it look better, apply a coat of latex paint.

Minor cracks are not a problem, but if it's seriously damaged -- especially if it turns to a dust-like material -- it should be handled by a professional.