Microsoft Touch Mouse
Traditional mice have flirted with touch-based scroll bars for at least four or five years, but we've only had full-surface touch-capable mice since Apple debuted the Magic Mouse in 2009. Microsoft followed with its own Touch Mouse last year. Logitech's M600 Touch Mouse is the latest contender.
None of these mice works as intuitively as a smartphone, and they all still rely on a traditional spring mechanism to register clicks. They're not bad, though, and with a few simple gesture systems, they're all easy enough to pick up. As the category matures, perhaps after touch-focused Windows 8 launches later this year, we may start to see some more-ambitious touch mice. I'd settle for pinch-to-zoom.
Below, the three currently available full-surface touch mice. Perhaps you already have a favorite?
Apple Magic Mouse
Apple was first on the scene with a true touch-input mouse in 2009. The shape of the device is cramped because of its narrow design, but at least the Magic Mouse has the touch basics down. Vertical and horizontal scrolling feel natural, and the 360 panning feature is great as well.
The Magic Mouse also supports the same basic "swipe" gestures as Apple's MacBook trackpads. You can slide two fingers across the surface for forward and backward Web navigation, or to advance or replay media content. The touch input isn't quite as robust as on a smartphone, since you can't pinch to zoom, but all in all it works well.
Apple sells the Magic Mouse for $69, although you can find it for under $50 if you shop around. You can also look into Apple's Magic Trackpad, which brings a MacBook-style trackpad to your Apple desktop.
With the M600, Logitech seems to be banking more on looks than improved functionality. The M600 has basic navigational input for vertical and horizontal scrolling, and it also supports Logitech's Flow Scroll software, a browser add-on that makes scrolling feel as smooth as on a smartphone. Other than those two simple-yet-well-done features, this mouse doesn't use touch input to any great advantage. With no other specialized gestures, the $69 M600 Touch Mouse offers no input functionality you can't also find in a $45 mechanical mouse.
The M600 is a member of Logitech's Unified device family, which means it can pair with up to five other USB peripherals using a single USB microreceiver. That's a fine feature, but not unique to the Touch Mouse.
Microsoft Touch Mouse
Microsoft's Touch Mouse is just as ambitious as Apple's Magic Mouse, if not more so. That makes sense, given the Touch Mouse's roots in Microsoft's ongoing touch research project.
Like the other touch mice, the Microsoft Touch Mouse offers basic horizontal and vertical navigation, but Microsoft took the touch input a step further by adding a gesture system designed to let you take full control of your desktop's application layout.
The hierarchical touch system in the Touch Mouse responds differently based on the number of fingers you use. A single finger lets you navigate around an application, as normal. Two fingers lets you position the application window within the Windows desktop. Use three fingers and you can see all open applications, for when you need to move back and forth between them.
Microsoft's gesture system is just shy of feeling immediately comfortable, but you should get it with a few minutes of practice.
The suggested retail price for the Microsoft Touch Mouse is $80, but you can find it for $50 or less depending on the retailer.
Compare these products side by side.