It seems to me that the computer mouse is often almost an afterthought, or even gets no thought at all, when configuring or setting up a computer. In many cases (I might even go so far as to say in most cases), when I have been helping someone order or install a new system, they say "I can use the mouse from my old computer", or "I have an old mouse in the closet somewhere, I'll use that". I can thnk of two good reasons NOT to do this - first, both the technology and ergonomics of mouse design have been steadily improving, and a mouse that is a year or two old (or a lot more) is honestly nowhere near as good as those available today. Second, even a mouse that is good in one situation, with one computer, might not be well suited to another situation.
The technology part is fairly easy to illustrate - looking back at obvious things like the switch from mechanical tracking (the little ball that used to be in the bottom of mice) to laser tracking, the development of cordless mice and subsequent improvement in the quality and reliability of cordless connection, and of course the steady improvement in their shape and feel, making them easier and more comfortable to use. When I was cleaning out my office recently, I pulled no less than four old mechanical, corded mice out of one cabinet, and just shook my head as I thought of how much they have changed.
On the other hand, I have recently had several good examples of how choosing "the right mouse for the job" can make things easier and more pleasant. I wrote recently about installing UNR on a very old Eee PC. That system had a touchpad with no buttons, which is a miserable way to have to try to work, so obviously we needed to add a mouse. I used a "standard" cordless mouse when I was loading UNR, and while that worked ok, the USB receiver is about the size of a typical "thumb drive", sticking out of the side of the netbook. Because the point of a netbook is to be very mobile, both around the house and on the road, that thing sticking out of the side is just begging to be broken off, damaging at least the mouse and very possibly the netbook as well. When I gave my neighbor a Logitech VX Nano, which has a very small USB receiver that sits almost flush against the side of the netbook. Besides solving the potential break-off problem, I also happen to like the VX mouse a lot, it is well designed, has a scroll wheel and forward/back buttons, and feels good in the hand. Very nice.
With the HP Mini 2140 netbook that I just delivered to another friend (more on that soon), the situation was a little different. I initially thought of just getting another mouse with a "Nano" reciever (Logitech has several different ones now), but then I remembered that the 2140 has integrated Bluetooth, and that works quite well with Ubuntu. Using a Bluetooth mouse would get the same benefits of cordless connection (convenience and comfort), but would not take up a USB port (the 2140 only has two of them). So this time I picked up a Logitech V470 cordless Bluetooth mouse. It connected to the 2140 perfectly on the first try, it reconnects smoothly after shutdown/reboot, and it works great. Another problem solved! By the way, Logitech has a new Bluetooth mouse the M555b, which looks like it might be even nicer, but it is not available in Switzerland yet, so I can't try it...
My own relatively new nettop (Dual Atom desktop) system also needed a mouse, of course. In this situation, because the computer is simply sitting on my desk, the worries about breaking off a larger USB receiver are much less, and in fact another interesting factor comes into consideration. If I want to change the mouse for some reason, and I am groping around on the back of the system to take out the USB receiver, it is a lot easier to find one that is thumb-sized than the little Nano!
Last, but certainly not least, my own HP 2133 Mini-Note. I have a strong personal preference for a trackball rather than a mouse, so I was very pleased to find the Kensington Slimblade Trackball Mouse. This little gem can actually be used as either a trackball or a mouse, and it connects via Bluetooth so once again it saves a USB port! Good stuff.
If you are buying or setting up a new computer, give a little thought to the mouse (or trackball), rather than just dragging one out of the closet, or just accepting and using whatever low-priced mouse is tossed in "free" with by the supplier. There are a lot of good options available, and they generally aren't very expensive. You can make things a lot easier and more pleasant by choosing the right mouse for the job!