As for grass, I've had some success with Jonathon Green Shady Nook.
I've used it on the north end of my house has a sort of alley way,
with woods forming the other side, about 15 ft away. It gets very
little sunlight. I've overseeded for several years and each year it
gets better, though it's been a long process. I can only seed it in
the spring, which is when it gets the most light.
However, I'd also be interested in hearing about other plant
alternatives, as I've considered going to laying down some stepping
stones and surrounding with some other shade loving plant.