Newegg has the Logitech G400 USB Wired Optical 3600 dpi Gaming Mouse for $40 - $10 off with coupon code EMCXTWS66
[Exp 3/20] = $30
with free shipping. Features 1000 reports per second, consistent response ratio, 400-3600 dpi range with single button switching, and eight programmable buttons. Amazon
has it for the same price.