Woot offers Ninestars Infrared Motion Sensor Trash Can 21 Gal. with Auto-Open Function for $29.99 (orig. $79.99). Free shipping for Prime Members.

Product Description:
The 21 Gallon Auto-Open Infrared Trash Can by Nine Stars has an infrared motion sensor and a hands-free automatic opening lid to make trash-throwing easy, hygienic and efficient. It boasts manual open/close buttons, a power-saving on/off switch and a garbage bag retainer ring to keep the bag secure. This stainless steel trash can is rust-proof and easy to clean. The hidden battery compartment requires 4 "D" batteries (not included). 

• Hands-free lid opens with a simple wave of the hand
• Advanced infrared technology preserves battery life
• Non-skid base protects your flooring from scuff marks
• Removable ring liner keeps trash bag securely in place
• Built-in manual mode keeps the lid open longer for bigger cleanups
• Commercial-grade fingerprint resistant stainless steel
• Large opening and capacity to handle all your household trash needs with ease
• Trash and recycling features include Finger Print Resistant, Heavy Duty, Odor Seal, Removable Liner