Sometimes, you are just drawn to a technology or a tool, there's no
explanation, and there's no going back. That's the way it was with me and
trackballs: I'd only had a laptop for a few months when I discovered
trackballs, decided it was my cup of tea, bought one, and have been using them
exclusively ever since. In that time – almost fifteen years, at this point
– I have used a lot of different trackballs. Each one is almost great, but
missing one thing. This is the story of my quest for trackball nirvana.
Kensington Orbit My first trackball was a Kensington Orbit and I'm wildly
nostalgic about it for that reason, but because it was mechanical, not optical,
it wasn't actually the best device. You can still find them on ebay once in
awhile! Look for the device with the blue ball and white body. I frequently had
to lift the ball out and scrub the rollers with a fingernail or toothbrush.
Eventually I dug a little notch in one of the rollers that prevented the ball
from turning properly, and that was the end of that. Mechanical pointing
devices, mice included, suck, and I'd never buy another mechanical trackball
either. The optical technology is just too much better for me to shed any tears
over this old roller.  So I replaced it with a newer model Kensington Orbit,
and was immediately thrilled. The thing sits well in your hand, with a low
profile; you left click with a thumb and right click with your third or fourth
finger, and you can use the combination of your index, middle, and fourth
fingers to manipulate the ball, giving pretty extraordinary accuracy. It began
to annoy me, though, that it had no natural way to scroll up and down through
documents, and I began wanting a trackball that allowed for scrolling. Though I
replaced it with newer trackballs, I kept it around and still use it from time
to time: it still amazes me with how comfortably it fits in my hand. 

Logitech Trackman Wheel

This thing has a lovely scroll wheel right between the buttons. You work the
buttons with your index and middle fingers, and the scroll wheel has a nice
weight and is comfortably positioned between them, which makes it very nice to
use. But to put the wheel and buttons up front, they had to move the trackball
to the side, where you roll it with your thumb. The device has a lovely, arched
shape that contours very well to your hand and is comfortable for long
stretches of time, but I found manipulating the ball with a thumb to be
tedious. Not only is it harder to use accurately but I actually find my thumb
getting tired after a long day at work -- for graphics, in particular.

Kensington Orbit Scroll

I'd liked my other Kensington so much I thought this would be the magic ticket,
but no. Instead of simply adding the scroll ring to the previous design and
leaving every other aspect alone, they actually changed the device's general
shape. The Orbit Scroll is a bit higher. You still use buttons with your thumb
and middle finger like the other one, and manipulate the ball with your index,
middle, and fourth fingers as before. I find that, strangely (although it's not
a problem), I manipulate the scroll ring with my thumb and fourth finger, which
is a strange combination. It's not bad, but somehow I wish they'd just left
well enough alone with regard to the previous design, which I had loved so much
and which had been so comfortable. 

Adesso

An experimental purchase from a previously-unknown company turned out badly. On
the plus side, it's got a big trackball up front and a scroll-wheel on the
side. That seemed like the perfect combination, and perhaps it would have been
had the entire device's shape not been so off. It's a broad, flat thing but
retains a high profile, so it feels a bit like putting your hand on top of a
book, or something. The buttons are perhaps too far forward, but whatever the
issue is with the buttons, I conclude they're in the wrong place because it's
never easy to reach them. I first found myself clicking with an extended first
finger, which was a bit awkward. But clicking with a thumb didn't quite work,
either. On the plus side, the scroll wheel on the side is quite handy and works
well, but it's my least favorite trackball when compared to every other
trackball on this list. 

Logitech Trackman Marble

This is potentially the most comfortable trackball I've ever used, which is
surprising because neither takes the shape of a cupped hand (like the Logitech
Trackman Wheel) or a low profile, flat-palm shape like the Kensington Orbit.
The ball is so exposed you have a huge surface to grasp for manipulating it,
and it's got a bit of weight, so you can get the ball spinning and throw the
mouse from one side of the screen to the other. It's got two inset auxiliary
buttons in lieu of a scroll wheel, though, which is hugely disappointing. On
Windows you can program them both using Logitech's driver. Amazingly – and
this is a second disappointment – while you can choose "page down" as one
option, you can't choose "page up" for the other button. With that exception,
this is my favorite and potentially most comfortable trackball, and it's got a
lovely click action on the two main buttons that make it a great trackball to
use.  When I lost one back in '08, I wasted no time in buying another model of
the same type.  That alone says a lot.

Logitech MX Ergo:
	 Like: It is truly ergonomic and comfortable, with a clever pivot-base
that provides two angles and a rubber foot that adds a third.  To my surprise,
I chose the most extreme angle, which puts the keys toward the side.  It really
is comfortable; almost like holding a joystick.  The Logitech Options software
allows you to program keys almost without limit.  I was able to map those two
little buttons to the left of the left mouse button to page up/page down
respectively, which is much appreciated and super useful.  Wireless is nice:
it's my first wireless device, and I like it better than I'd expected.  (Need
to remember to turn it off at the end of the day, though, which is new) The
"precision mode" button that controls sensitivity of the trackball is unique
and appreciated.  I don't use this (yet) but love the idea: you can use this
with two computers simultaneously, and it's got enough RAM onboard to permit a
cool trick: you can copy text from one machine and then paste it on the other
machine.  In effect, this device becomes the bridge - super clever.

 Dislikes:
 As usual, setting it so your thumb alone controls the trackball is less
comfortable than devices where you can use the whole hand, multiple fingers,
etc.  Every time I restart use of a device with this layout, I am initially
annoyed by it until a day or two of usage, when I get accustomed to it.

Kensington Slim Blade:
Likes: The flat, low profile device is very comfortable.  The biggest ball of
any device I've used, and it's great: it's got better inertia than most, so you
can throw the cursor across your desktop.  And after switching between devices
where you move the ball by thumb, and devices where you move it using your
other fingers, I find this is the more comfortable tool in the long-term.
Wasn't sure how I'd handle four buttons, but because you can program them any
way you like, it was easy to make two of them page up/page down, and
furthermore easy to map left click/right click to the buttons where my fingers
landed naturally.  Their innovation in which rotating the trackball in place to
scroll is very clever and works well
	   
Dislikes:
The 4 buttons are placed somehow in a way that didn't quite work for me.  I use
the large, lower-right button very little, though it's clearly supposed to be
one of the most important buttons.  That's because my fingers naturally fall on
the top-right.  Something to do with large hands maybe. I wound up binding both
right-hand buttons to "left click" so I could position my hand in multiple
positions and still access context menus. It's also one of the louder
trackballs I've ever used, which I now notice more than I did at first.