Here is a speed ramp I made for my back yard for when it snows so I can ski a rail before the slopes open:
http://i1093.photobucket.com/albums/...730102008a.jpg
http://i1093.photobucket.com/albums/...a1/skirail.jpg
Here is a video of the setup.
http://www.youtube.com/watch?v=VnqIijqohUE
The only thing I would change is to make the rail longer.
