encourage moss and kill grass/weeds

May sound weird: but i want to encourage moss in an area ( shady) and eliminate the small amount or grass and weeds. Any way or products to do this?

This site may be helpful:

http://gardening.about.com/od/gardendesign/qt/How-To-Grow-Moss.htm

I've taken a handfull of moss along with some buttermilk and put it in the blender. (Don't let your wife see this.) Then sprinkle, splash or paint it on the surface you want it to grow. It going to have to be a damp/shady place for it to take off.

a bit late but thanks to posters - site will be helpful

I have yet to find any information on products that might control broadleaf weeds but not injure moss. Anyone have any suggestions?