Amazon offers Prime members the Lifx 800 A19 WiFi LED Smart Bulb, model no. BUL-11-A19E26-W, for $19.95 with free shipping. (Non-members can spend $49 to bag free shipping; otherwise, it adds $6.81. Best Buy charges the same with free store pickup.) That's the lowest total price we could find by $8. You can adjust the shade and brightness through WiFi via its smartphone app or Amazon Alexa.