Intellimouse Wireless Explorer
This has got to be the ultimate mouse, or close to it. Not only is it cordless, but no installation is required, either. You just plug it in and it works with a base station that can be placed three feet away without reception problems. Transmission is via radio waves. Two batteries power the mouse and the manufacturer promises that they will last for four months, using advanced energy-saving technology. In fact, it detects the presence of your hand and starts up as soon as you use it. However, in practice there is sometimes a short pause, but you get used to it. We haven't had to time to check how long the batteries last, of course, but even if they only last two months like Logitech's batteries, that is perfectly acceptable.
The ergonomic shape is designed for right-handers exclusively, especially those who don't have massive paws. As soon as a device reaches the optimum in ergonomics, it becomes less usable for those at the extreme ends of the spectrum. On the other hand, no pun intended, right-handed people whose hands are not overly large will find it as comfortable as can be. Despite its rather large size and the weight due to the batteries, it fits naturally in the palm of the hand and can be easily manipulated without ever tiring the user. The four buttons and the knob can be operated smoothly and precisely. Furthermore, it benefits from the same technology used by other Intellimice, so no worries on this score. It is thus the perfect mouse, or rather it would be if it didn't cost $65, which is quite steep. Furthermore, like the Logitech models, the cordless mouse does not convince me as being the best device available for playing FPS and other high-speed games such as Quake or Red Faction. I find the response time to be slower than with a conventional mouse.