As one of its daily deals, Best Buy offers the Razer DeathAdder 2013 Gaming Mouse, model no. RZ01-00840, for $39.99 with free shipping. That's the best outright price we've seen and a current price low by $23. (For further comparison, in June we saw it bundled with a $50 Steam gift card for $70.) It features a 6400 dpi 4G optical sensor, five buttons, gold-plated USB cable, and illuminated scroll wheel. Deal ends today.