Amazon has the Logitech MX620 Cordless Laser Mouse (Black) for $45.75 with a $20 MIR and free shipping.
Features:
* Precision laser tracking for smooth, responsive cursor control
* Fly through long documents at hyper-speed or shift instantly to precise click-to-click scrolling
* Interface: USB
* 2.4 GHz digital cordless technology ensures seamless wireless connection
* Advanced one-touch search and foward/back buttons
* Smart power management means up to 1 year battery life
* Powered by 2 AA batteries (included)
* 5-year mfr. limited warranty
Amazon.com: Logitech MX620 Cordless Laser Mouse (Black): Electronics $20 MIR
Logitech MX620 Cordless Laser Mouse (Black) $26 AR + FS 
