I have a pair of packable Columbia rain pants (and jacket) I'll either wear or throw in my backpack when there's the potential for a cold downpour. For light rain something water resistant is good enough.

My legs will get damp no matter what though, -if not from rain then from perspiration. It's OK, I change at work and my goal is to stay warm, not necessarily dry. If you're riding in your work clothes, then it's more of a challenge.

For my feet I have a pair of water proof (mostly) hiking boots. They're not my favorite things to ride in so I'll often just wear wool socks and my regular cycling shoes. My feet will get wet so I bring an extra pair of socks for the ride home and shove paper in my shoes to help them dry while at work.