Microsoft Explorer Mouse
They might seem old fashioned, but trackball mice have one thing going for them: so long as there is a solid surface, you can always use a trackball mouse and it will work. However, when you need high precision tracking and speed, optical and laser mice are king--but such mice have problems with or can't be used on reflective, glossy, and transparent surfaces.
Microsoft's BlueTrack technology, which is found in the company's Explorer Mouse attempts to solve some of the tracking problems with optical and laser mice. The Explorer Mouse uses specialized lenses and a blue LED (hence the BlueTrack name) to allow it to have better accuracy on a wider variety of surfaces.
In my testing, the Explorer Mouse performed admirably just about anywhere I happened to put it, be it on leaves, LCDs, even on my hair. However, that's not to say there isn't a surface that causes problems for the Explorer Mouse; it was easily stymied by CD jewel cases, as well as the underside of CDs, and the box for a new MacBook Pro.
My "daily driver," Apple's wired Mighty Mouse ( Macworld rated 3.5 out of 5 mice ), had even more trouble with the surfaces the Explorer Mouse struggled with, so it's clear BlueTrack is an improvement, but not always a marked one. My Mighty Mouse also worked on the LCD, on the leaves, and in my hair, though with a lesser degree of accuracy compared with the Explorer Mouse.
The Explorer Mouse definitely feels great, at least in my hands. It's significantly bulkier and more sculpted than the Mighty Mouse, but it feels solid, and my hand conforms rather easily to its contours. While it's obviously designed for right-handed use, the Explorer Mouse is usable for lefties, but the two auxiliary buttons are awkwardly placed. Unlike most scroll wheels, this scroll wheel isn't notched; rather, it spins freely. This is great for Web browsing and word processing, but it can be a bit too speedy for apps like iTunes.
The mouse comes with a single rechargeable AA battery and a charging cradle that fully recharges the mouse in a few hours; I found that charging the mouse for as little as 30 minutes was enough to last a day's worth of work. The battery indicator on the mouse flashes red when it needs to be recharged, and throbs green as it is charging, finally reaching solid green at full charge. While it would have been nice to see a more sophisticated and graduated indicator, Microsoft's choice works perfectly fine.
The software bundled with the Explorer Mouse installs the Microsoft Mouse preference pane in System Preferences, a handy set of easy-to-use tools that allow you to customize the mouse's behavior in different applications, and choose special actions from a plethora of choices. The one quarrel I have with the Microsoft Mouse preferences is the inability for the user to test out the programmable auxiliary buttons while the preference pane is open.
Macworld's buying advice
The Explorer Mouse is a solid mouse. It feels great and performs well. The BlueTrack technology that it uses isn't so much of a great leap forward compared to that in Apple's latest offerings, but it's still an improvement. If you're constantly working on nonstandard surfaces, then the Explorer Mouse is probably right for you.