There a lot of great groundcover sedums out there.

I'm also in favor of a grass less yard. I've put in a few different ground covers. My favorites are the low growing sedum. Check out the nurseries there are quite a few to pick from. Once established they take off fast.

Creeping thyme, ground hugging dianthus, hardy geranium, ajuga, gypsophilia repens,

My new favorite ground-cover is Sweet Woodruff (Galium). It is very short - 3 inches, spreads but supposedly is easy to pull out, and bears little white flowers in spring. The best thing about it is that if you pick it and put it to dry, in three days it smells heavenly - a very long lasting wonderful potpourri.

I have thyme-leaved speedwell, Veronica serpyllifolia, that grows well in a morning-sun spot in our lawn. It isn't bothered by foot traffic and grows thick enough to eventually choke out grass. In late spring and early summer, it blooms with tiny white purple-streaked flowers that rise maybe two inches above the leaves. It grows by prostrate stems that root at leaf nodes. Leaves are oval and opposite.

I would recommend growing it if you have a spot with moist partial shade. Roots might be too shallow for dry sun, though I haven't tried it there.

I don't know if Veronica serpyllifolia is offered in nurseries, but a yellow-leaved variety of a similar species, Veronica repens 'Sunshine', will be sold at the Friends School sale. They're also offering Veronica liwanensis, another creeping species that I haven't grown yet.

Here is a link that might be useful: Speedwell, Golden Creeping, 'Sunshine'

(Apologies to forum authorities for the link -- it probably counts as advertising. I thought I had removed it before I posted, but apparently it didn't work.)