Kensington is known for pumping out an endless array of tech add-ons, from iPod docks to laptop cases. Most are perfectly functional, but not exactly stylish, which makes this new line of travel mice (including the larger Ci70 LE and the slim Ci75m) especially interesting. Physically similar to the 0.7-inch-thick Ci75m, the $40 Ci85m is the first ExpressCard wireless mouse we've seen. Instead of a USB dongle, the mouse instead connects to an ExpressCard/34 receiver. The advantage is the purportedly instant connection, but the fact that you have to carry around an extra part (the ExpressCard itself), makes us less fond of this mouse than its USB-powered cousin, which can hide its receiver in a slot on the underside of the mouse. It's an intriguing concept, but unless you have a specific reason for wanting an ExpressCard mouse (we can't really think of one offhand), stick to the slightly cheaper USB model.
For a travel mouse, being easy to carry and use is a key feature. We liked the Ci85m's small size and slim profile. While modern desktop mice typically include at least an extra thumb button or two, the Ci85m has just the basics--left and right buttons and a scroll wheel. The cover (held in place with three tiny magnets) easily pops off, perhaps a little too easily, for inserting the two AAA batteries (thoughtfully included), or accessing a tiny built-in USB cable that lets you use the mouse without the wireless receiver. The cable measures 25 inches in length, which should be more than adequate. On the bottom of the mouse, a small sliding cover exposes the laser. Sliding it closed shuts off the mouse to preserve battery life.
The Ci85m's length and width are the same as the USB-powered Ci75m--4.25 inches by 2.5 inches by just 0.7 inch thick--and it could easily slip into a shirt pocket, not that we recommend carrying a mouse around in one's shirt pocket. The shallow body and buttons can take some getting used to, and it's not the most comfortable mouse for long-term use.
The Ci85m's main selling point is its quick-start feature. While most wireless mice require Windows to recognize that you've plugged in a new USB device and do a little behind-the-scenes housekeeping before the mouse will start working, the Ci85m did indeed connect the moment we plugged its receiver in. It was impressive, but we can't recall ever being particularly put out by waiting for a few seconds the first time we plugged a USB wireless mouse into a new laptop. Plus, it takes about as long to find the ExpressCard slot on your laptop (if you even have one), pull out the placeholder dummy card that's probably already in there, plug the mouse's receiver card in and extend the tiny antenna built into the card, as it does to plug in a USB receiver and wait for your laptop to recognize it. While the ExpressCard receiver is an extra piece of hardware to carry around, once it's inserted in your laptop, the antenna can retract when not in use and the receiver can be permanently stored in the laptop, out of the way.