I am now on my second Logitech Trackman Marble Mouse. My husband bought me both of them and I have them at different computers. At first glance you think this thing is a spaceship from some SciFi movie and in fact, my mouse is named, "Moya" for anyone who has seen Farscape.
I am a Graphic Artist and Web Designer and pretty much live on my computer. Well, using an old fashioned mouse really was hurting my wrist. I adjusted my seat, my desk and even tried a gel wrist pad, but nothing was working. So a past co-worker of mine bought one of these and when I first tried it, I thought he was nuts. I mean, it really took me about a day or at least several hours to get use to using this mouse, but let me tell you - there is NO turning back for me - EVER!
The thing I love the most about my mouse is the ease of use and lack of moving it around. I don't need a mouse pad and there are no little wheels inside that get dusty. When it's time to clean my mouse, I can feel the ball become a little sluggish and know that dust is in there. So you pop out that red ball and just wipe the 3 little tiny contact points and pop the ball back in. It's just so easy to clean.
My mouse doesn't slide on the desk either because there are 3 rubbery pads on the bottom to keep it in place.
I can set the buttons on either side to do shortcut tasks - like the top left little button moves me back a page when I click it. On the other side, the right little button turns into a 4 pointed scroll and allows me to move around the page without using the scroll bars on a web page. The large left darker grey button is my "clicker" and the larger button on the right side is the "right click" like on any other mouse.
Now I know this mouse is holding it's value and still sells for around $60, but it is so worth it. And if you were on the computer as much as I am and suffered the beginnings of carpal tunnel, you'd know what I am talking about.
There are also newer versions of this mouse but I prefer this style that allows my hand to sit on top. I barely touch it when designing or clicking through a web page and it's ergonomically correct for your hand placement too.
Update On Apr 20, 2010: I am about ready to order my new laptop and know that I will still be using this mouse. I am so addicted to it because of the ease of use that I can't put it away. I know it looks odd and the price is still holding around the $60 mark, but it's definitely worth every penny!
Update On May 04, 2010: Ok, so I got my new laptop and yes, I am using my trackball still. I can't get rid of it and it's so gentle on my wrists. I can't get use to a laptop "tiny travel mouse" because just like with any regular mouse, you have to always keep moving the thing around! My wrist just can't take that kind of movement or I will be facing surgery. I will use the touch pad when I absolutely HAVE to. But you can bet my trackball will be tucked away in my bag when I take it out the door!
Update On May 25, 2010: Even though I got my new laptop, I am still using this mouse. I knew I would because it's so easy on the wrist. It limits the movement of your wrist and helps so much when you are on the computer most of the day. Of course there will be times when I can't use it but for the most part, it's connected to my laptop.
Update On Aug 07, 2010: My trackball is the best piece of computer equipment I have ever had. I can not recommend this mouse more! With all of the web design and graphi artwork I do, this truly keeps my wrist from hurting because there is very little motion needed when using it.