Palmtop computers are really quite useful. They extend the info you have to where you are, instead of tied to a laptop or desktop. They are great for keeping your schedule and phone/contact list close at hand. Now that I am Flight Instructing as well as working full time, I find that it aids me tremendously to keep my act together. The largest hassle that I find with these devices is that I don't use any of the popular scheduling or contact databases. Instead I use my own ... which means that I have to write my own Conduits (or equivalent) to allow this data to be "synchronized". I find the tools to do this somewhat lacking, since they aren't tools which allow arbitrary use, but rather applications with their way of doing things and not much else.
I'm continually amazed and dismayed at what I see in the palmtop computer market. Things that are half-baked, other things that charge fees beyond their value, and yet.. You have computers that sit in the palm of your hand and have more CPU power and memory than the largest PDP-11 system ever built. Some people don't consider palmtops to be computers. I certainly consider an PDP-11 to be a computer, and if something has more CPU and memory than one, I would think that it is a computer!
Though I don't have one (yet) I favor the PalmOS machines. Their small size and the wide variety of software that is widely and inexpensively available for them make them quite attractive. There is also a decent selection of hardware available. The new Sony Clie 760 with a 320x320 screen resolution even compete with other palmtops, such as those Pocket PC models, whose name to fame is a hires display. The big problem I see with the Palm platform is twofold. One is the the lack of multi-tasking between applications; you can't just switch between one application and another. No looking up a phone number when you are entering text, for example. However, the between application coupling may mitigate that somewhat, but that is only for special purpose, not general, use. The other problem is the lack of support for commodity hardware in the Palms. For example, wireless 802.11b Ethernet so I can access online resources when I am in my home, at work, or in other places with Wireless Ethernet. The only ethernet support I know of is the ethernet cradle, which is only available for near-obsolete versions of the machine.
The Hand-Era is a pretty nice machine in its own right. Instead of having a dedicated grafiti area, it has a much larger screen with a virtual grafiti area. The great thing about this is that it gives you larger screen real-estate to use when you aren't using the stylus input area. Someone at Steep&Brew showed this to me. It made all the difference when reading and editing textual documents; you could have enough text on the screen at one time to be really useful. Oh, and the thing uses the older Palm-III style interface that everyone in the world makes peripherals for and that you can hack into with simple serial hardware too.
I hope Palm gets their act together; if they don't the only thing left to use will be Microsoft Pocket PC boxes running the aptly named WinCE, or whatever they call the modern version of that mess.
Palm seemed to have everything going for it ... then starting in 2003 they just seemed to give up and go about making themselve a company that is untenable.
Sharp Electronics makes something different .. the Zaurus. It orginally was a Palm form-factor PDA that runs Linux. These days it is on more capable hardware, but of the same form factor and even greater functionality.
Yeah, yeah. Despite the spiel above it looks like Palm is doing its best to kill of its own market. It has increased licensing costs and killed off several manufacturers of excellent Palms. The only Palms you can purchase these days are behemoths that rival Pocket PC systems in cost, size, and miniscule battery life. Palm is killing themselfes off.
There are a number of fine hardware-oriented software that have become available for the Pocket PC recently. With the excellent reflective and backlit and bright display on the Compaq iPaq, the PocketPC platform is looking to be more attractive -- despire the M$ problem.
Both of these platforms have a good deal of aviation software. Some of it is so-so... but there are some fine GPS and Artificial Horizon software and hardware out there which is great for backup use on IFR flights. That can be found in the Software Section of my Flying web info.
This just has info about cables, various non-mainline (to my aviation brain) GPS units, and such. Heck, there are even BlueTooth GPS units which don't need a cable to transmit the GPS data to your palmtop!