LogitechTrackman Marble Trackball – Wired USB Ergonomic Mouse for Computers, with 4 Programmable Buttons, Dark GrayCarbon Neutral Certified by SCS Global Services

I've been using this Logitech Trackman marble mouse since the late 90's, and been using personal computers since 1984. In that time, we've worn out one Logitech Trackman marble mouse after almost ten years(the first-- left button started being erratic), but bought several for our multiple computers. Once you've used one you'll never want to go back!There's several advantages:1..The big one is accuracy. If you do ANY graphic work at all, even just fixing red-eye on photos, this is *the best* mouse to use. It becomes so intuitive and fluid, it's as agile and precise as your eye-hand coordination allows. It doesn't "get in the way" like a regular mouse.2..Space saving. Even with a cord, this thing takes up less space than a wireless mouse, because it doesn't require movement. It also doesn't require a mousepad and works anywhere-- on your leg, on your chair arm, on a clear glass desktop. (I love it so much, I use it as my mouse with the laptop that I'm on for 8-10 hours a day! Yeah, it's that good.)3..Aching wrists/fingers will be a thing of the past. This mouse is much more ergonomic and comfortable.4..Versatile. Got both lefties and righties in the family? No problem! The Logitech software adjust for either with just a couple of clicks, and the mouse itself isn't shaped to favor one hand over the other.5..BUILT LIKE A TANK!! Like I said, in ten years of heavy, heavy use by three computer nerds, with hundreds of thousands of clicks or more on the original unit, we wore out exactly *one* of these mice. And yeah, that mouse fell off the desk a few times, and the ball went bouncing across the floor probably a few times a month (One of us is a bit of a klutz). That said, you're less likely to drop it because you're not having to constantly move it.6..User satisfaction. Everyone who uses one never wants to go back. Ever.7..Excellent for those with limited hand movement. If you can move your thumb to click, have minimal movement in your arm and can rest your fingers on the ball, you can probably use this mouse. The four buttons can be specially programmed (say, if you've only got click-ability with your thumb, or your pinkie, for instance) and are configured so that accidental clicks aren't a huge problem.I can't speak for the wireless version of this mouse as I've never used or owned that model, and I *don't* recommend the version that puts the ball under your thumb-- that one *hurts* to use for very long.I hope Logitech NEVER stops making this mouse, because I have never found another of any kind, wired or wireless, that is so accurate, comfortable and well-built!

This mouse is a masterpiece. This mouse will be in a museum someday. I hope that Logitech never stops making this mouse.I have used many different types and brands of input devices: mice, trackballs, touch pads, gyroscopic air-mice, wacom tablets, etc...This is the most comfortable mouse for general use. I can use this mouse for 8 - 10 hours straight without any problems. The key to this mouse: You rest your hand on top without squeezing the sides of the mouse. The design of the mouse/trackball facilitates this. Your palm gently rests on top of the grey base which keeps the grey base from moving.With a typical mouse, I will grip or squeeze the sides of the mouse in order to move the mouse and also when clicking down on the mouse. I have found that this gripping/squeezing action is what causes me to get carpal tunnel syndrome. In order to prevent wrist pain, I have to be consciously aware of how I am using a mouse whenever I am using a normal mouse. The Logitech Trackman Marble Mouse does not require this conscious effort or awareness.Pros:Simple to use, plug and play if you don't use the 2 middle buttonsYou can flick the trackball to quickly and easily move your cursor anywhere on your screen.Much easier to use than a typical mouse or typical (thumb) trackball after you get used to it. It took a couple of weeks to get used to this. Use it for a couple of weeks to give it a fair chance.Requires less desk real estate than a mouseInexpensiveCons:The left click button wears out after 6 to 12 months depending on usage. My computer is used daily. Infrequent users may have this mouse for years.The small white balls that the red trackball sits on top of eventually get stuck or break. The red ball will no longer move smoothly after this. Again, keep in mind that my computer is used every day.With heavy usage, the grey paint eventually wears off the buttons and base. But maybe this is more of a Pro, because the paint wearing off indicates that the mouse has lasted closer to a year than 6 months (Built-in mouse replacement indicator).Care:Remove the red trackball every so often and clean out the lint from the white roller balls.Remove any dirt, sweat, or oil from the red trackball at this time.Be delicate when putting the red trackball back or you may damage the white roller balls.Keep clean, the 3 rubber pads on the bottom of the mouse. Keeping the rubber pads clean will prevent the mouse from moving on your desk. This will in turn prevent you from constantly having to adjust the position of the mouse on your desk.