Best Buy offers the Logitech G502 Proteus Core Tunable Gaming Mouse, model no. 910-004074, for $59.99 with free 2-day shipping. (Amazon offers it for the same with free shipping.) That's the lowest total price we could find by $10, although we saw it bundled with a $50 Steam credit for $80 two weeks ago. It features five DPI settings, adjustable weight, center of balance and placement of weights, and 11 programmable buttons.