Microsoft's BlueTrack technology may have led to some pretty impressive mice, but they so far haven't dipped much under the $50 mark. That's now changed with the company's new Wireless Mobile Mouse 3500, Wireless Mouse 2000 and Comfort Mouse 4500, however, which all come in at less than $30, and promise many of the same advantages as Microsoft's pricier mice. As you can probably figure out, the three mice cover the cordless, portable, and corded bases and, with the exception of the gray-only Wireless Mouse 2000, are each available in a couple of different colors. All three are also available for pre-order starting today, with the Wireless Mouse 2000 and Comfort Mouse 4500 set to roll out next month, and the Wireless Mobile Mouse 3500 on track to ship in April.