Oops..Sorry
1. Add a plane
2. Scale to size you want
3. Add new texture
4. go to tab "mirror transp". Enable "Ray mirror" and "play with the values for "Ray mir (0.5)" and "fresnel (1.5)"
Setting blender GUI:
http://i174.photobucket.com/al ... LFS_Blender_mirror_II.jpg
"Result"
http://i174.photobucket.com/albums/w107/sir_tooby/UFR.jpg
Hope this is what you where asking for