Getting a mouse to track on a glass surface is the computer peripheral equivalent of cold fusion. By that measure, Logitech has accomplished the equivalent of Nobel Prize-worthy work, unleashing a mouse that can track just about anything (including glass.) Thanks to a technology called Darkfield Laser Tracking, the Performance Mouse MX works on ultra-smooth surfaces that don't have the natural imperfections that most optical mice require. Instead, the Performance Mouse MX uses its highly sensitive laser to analyze surface material such as dust and dirt, using grime as an analytical surrogate for the natural ridges and bumps on, say, a wood table.
The Performance Mouse MX also includes all the programmable thumb buttons, an adjustable super-fast or click-to-click scroll wheel, force-sensitive sideways scrolling (a first for mice), and recharging via USB. It's ergonomically sculpted (for righties only, sorry!) but, frankly, it's a bit on the big side. Lefties might check out the smaller and less full-featured but just-as-accurate Anywhere Mouse MX.
