Woot offers ELENKER BC2170625080003 Knee Scooter for $50 (orig. $84.99). Free shipping for Prime Members. 

Product Description:
ELENKER Knee Scooter with Basket Dual Braking System for Ankle and Foot Injured Bright Black

• Knee Scooter Function - Ideal for ankle or lower leg individuals recovering from a foot, ankle or lower leg as well as below the knee amputees
• Security & Stability - The scientific bottom frame can provide better support, ergonomic adjustable locking handbrake provide better safety
• Folding Design - The Steerable Knee Walker Scooter also features handlebars with a quick folding mechanism for easy transport and storage
• Comfortable - Using crutches requires extensive upper body strength, rubs under your armpits and is unstable. This knee scooter is made for both indoor and outdoor use, it is a hands free / pain free crutch alternative.