Pocket Clamshells ================= In my humble opinion all the Psions are not pocket computers: they are too big to fit in a pocket. The same applies to the HP 95LX-200LX (the size of these boxes is almost identical to the Psion Series 3 line). Also final versions of Linux-based Zaurus machines are too thick to be real pocket computers. Thus I see only two or three real candidates: 1. Sony Clie UX-50 2. Sharp Zaurus SL-C750 to SL-C860 3. Ben NanoNote No one is perfect. The tiny Ben is the most portable, the most compatible (being a Linux computer with a microSD slot and the MicroUSB port for charging) but is was designed to be cheap. It means the poor display (320x240 with single level of backlit), no sleep/resume and poor build quality (cheap plastics). The use of fairly modern Linux means not only availability of modern software but also that one experiences issues because of an insufficient size of RAM and the slow CPU. The combination of a small RAM, small screen and non-existence of pointing device makes use of GUI questionable. There even is a n OS with the X Window System available but it is both slow and impractical. The Zaurus (which is about 6-8 years older than the Ben) is much more powerful (2xlarger RAM and about 2xfaster CPU). It also uses older Linux-based system which is smaller and faster. It has a quite nice 640x480 screen and there is flawlessly working sleep mode. Only the on-board storage is smaller (128 MB vs 2 GB of the Ben). The building quality is simply incomparable and the keyboard is also much better (in terms of a feedback, a build quality and the layout). The main issue is limited expansion (a tiny offer of acceptable cards: there is no support of SD cards larger than 1 GB for example) and limited connection (no USB on most of models). Also the proprietary charging connector is not ideal. On other side the Zaurus has excellent keyboard (the C3xxx line has the best but the older ones have nice ones, too). And as teh only device from these three it can be actually used it a laptop mode - when sitting on the desk. Well, the Sony Clie is very different from those two. It was extremely well-built, it has some excellent features (backlit keyboard, for example) but it also has fatal flaws. For understable reasons it runs a PalmOS (version 5). On paper, it is the slowest one (123MHz Sony ARM CPU) but the lightweight OS makes the whole thing fast. The keyboard design is strange (the keys are in level of their surrounding - it looks nicely but it is harder to press). There is only one Shift. Albeit the layout is far better than the one on the Ben, the lack of the right Shift is surprisingly important. There are problems with system control as some operations require stylus and cannot be done from the keyboard. But it is probably a problem of the OS. The ugliest feature of the device is the charging: it requires use of a big dock (almost as big as the device itself!) and a big power supply. The dock has no data connection - it is only used for charging! The USB connector is located on the device body, not on the dock (as you expect, the device cannot be charged via the USB). So if a longer trip is planned and charging is expected then portability of the device is radically limited... One might argue that Zaurus also uses strange power supply - but there is no such dock and the power adapter is smaller. The use of a proprietary MemoryStick card is an issue, too but it is logical for the Sony. And now we have nice adapters for that (now I use a 512 MB microSD here via pair of adapters and it works well). Well, the Ben NanoNote. Feature-wise, it's the best: it can be charged via USB, it supports Ethernet via USB, it runs semi-modern Linux so there is quite good selection of software. BUT, it's building quality is low, the hardware is underpowered and there are design issues. Thus it's speed under X11 is terrible and even without them there is a strict limit what can be used (it the terms of necessary RAM size, screen resolution and so). But the terrible thing is it's battery life. It's actually OK (up to 8 hours of active use with a new battery, ut to hour on the WiFi) but there is no sleep mode. So one has to close everything and to turn the thing off when device is not used. That's not too comfortable. And the keyboard has it's problems: hardware quality (teh G letter often broke) and layout: it's qute hard to use it as a calcualtor because there are many modifiers (one for numbers, another for symbols like +*-%,...) so writing something like "y=sin(x+2)" is too slow.