If it is soft to the touch and the stem appear pliable and succulent, I'd guess sedum reflexum. Mine is just about to come into bloom (yellow). I have massive plantings of it, one of my fav groundcovers, and it has replaced mulch in many of my beds, both sun and shade.

The scale is not clear. Is it very small? Could be Sedum acre which is much smaller than S reflexum (aka S rupestre)

linaria..........I think your suggestion of sedum acre is probably right. I went out and looked at my beds of sedum reflexum, and the arrangements of the tiny needle/leaf is much more casual and less tight. I've grow sedum acre as well, and think I confused the two.

Thanks, folks. Based on photos on the web, I don't think that it is S. acre or S. reflexum. The homeowner reports that it never gets taller than one inch.