Did I say Fast? Extremely Fast!
How do you steer? By weight shifting.
How do you brake? You don't.
Brakes were invented by cowards.
This Extreme project is Extremely suited for the Extreme contest because your whole life would go Extremely fast before your eyes even if you close them bombing down that Extremely steep hill.
You can't buy anything like this but it's Extremely cheap and easy to build yourself.
Step 1: Parts & Materials
You will need:
Pair of used downhill skies you can buy cheap at second hand store. Take off all bindings.
Piece of plywood for the seat. I used cushioned seat from the old automotive creeper. Be creative.
1-1/4" Gray PVC 90deg Elbow, Schedule 80 - 3 pc (Look for electrical conduit)
1-1/4" PVC plug - 6 pc (look in plumbing, not all hardware stores have them)
1-1/2 x 1-1/2 x 1/16 thick Aluminum Angle - 6" long - 6 pc
Various nuts and bolts.
Step 2: Support Structure
Cut and drill Aluminum angles.
Attach 45deg fittings to the PVC pipe and align them on a flat surface.
Drill Fittings and pipe in place. Bolt through.
Align and clamp aluminum angles to the PVC pipe and drill in place. Bolt together.
Align supports on a seat, drill and bolt together.