Buy.com offers the Microsoft Wireless Mobile Mouse 3500 in Gold, model no. GMF-00046, for $9.45 with free shipping. That's a buck under our mention from last month and $3 below the lowest total price we could find for any color. This wireless mouse features BlueTrack technology (which purportedly works on more surfaces than optical or laser technology), a nano transceiver, on/off switch, and more.