Stepables:

http://www.stepables.com/

...specialize in ground covers. Some will hold up better to animal traffic than others. Even if you don't buy "stepables" there should be enough information on the site to give you a starting point for what plants work well as ground covers.

We've had

this taking over our front yard and I've let it grow. Although I have no idea what it is, but it does grow relatively low.

June, that's clover. It's a great groundcover, very drought resistent, pest resistant, and soft on the feet. You do have the keep the flowers mown if you want to avoid bees though.

We're spreading buffalo grass seed in our backyard. It has no known pests, is almost as soft as St. Augustine on your feet, and is incredibly drought-hardy. I think it only gets to 3-12" high unmown. It's a beautiful green-grey color, but it is a hot weather variety, so it turns brown after frosts.

Claire, thanks for the info! I actually just got a lesson on bees this past week. In the side yard - where we have other types of ground covers - I definitely stepped on a bee. I even got the full on swollen and bruised foot.

I've been stung by a bee before and nothing happened....so I wasn't expecting the swelling and bruising. Fortunately the clove I pictured is not in an area I walk much.