As one of its daily deals, MidnightBox offers this 10-Foot Retractable Dog Leash with LED Flashlight
for $8.95 plus $3.99 for shipping. That's the lowest total price we could find by $2. It features a thumb-locking mechanism and waste bag dispenser. Two AA batteries are required, but not included. Deal ends today.
Update: Tanga has it for $7.99 plus $2.99 for shipping.