Top Greener via Amazon offers its Top Greener TGDS Electric Light Dimmer Switch for $15.39. Clip the 20% off coupon on the product page to cut that to $12.31. Plus, Prime members bag free shipping. That's $3 under last month's mention, $10 off list, and the lowest price we could find. It features both single pole and 3-way applications. Deal ends February 6.