I have had a Sony Clie 710/760 for a year and a half and have become very dependent on it for a variety of business and personal tasks. It was a great machine with a vibrant screen in a truly pocket sized package. It was a little bulkier than the Palm 505 which was their color offering at the time, but the display was so much better on the Sony that It won out over the Palm for me. Besides database stuff, contact and appointment data and a calculator, it also allowed me to carry pictures of the wife and kids, play a few games, read ebooks and Avantgo, and occasionally listen to some tunes on an airplane. I picked the Palm OS as the devices seemed more compact than the PPC devices of the time and the Palm OS was supported on both Mac and PC platforms. Since I have a Mac for work and PCs at home this was important to me.
My Clie died suddenly last week. Or, well, it seemed ill and I accidentally killed it during surgery. Sony wouldn't work on it even out of warranty because I'd upgraded the machine to Palm OS4 which they don't support on a 710. So suddenly I needed a new PDA. There was no way I'd go the two weeks or more that Sony would take to repair it even if they would work on it.
I think the most bang right now is the newer Sony PEG-665C. It does everything my 710 did, but has twice the memory (16 mb) and twice the processor (66mhz vs 33) and is about 40% thinner with an even better screen than the 710. Because Sony is coming out with some new models in the next few weeks, the 665C has been reduced at Best Buy to $299.00. This is a tremendous PDA and with a 128mb Memorystick, you can get a couple hours of tunes to go with pretty good sounding hardware MP3 support.
As much as I like the Clie 665c, I ended up buying the Palm Tungsten T. It's also got 16mb of memory like the Clies but runs on Palm OS5, has a 144mhz Strongarm processor and built in bluetooth wireless connectivity. Unfortunately for me it uses SD memory, not memory stick, so my existing memory stick is useless. I think there are certain things I like better about the Sony 665s form factor in some respects, but the T has more forward looking technologies with the newer OS (not supported on the Sony T or N series), the wireless hook up and the stronger processor. The tiny size is pretty cool as well. Now if only I could find a cool case for it.
Sony has some larger OS5 machines NR & NX series), but they're too large to go everywhere with me like the T does, or even my old dead 710. Their top end stuff with the built in cameras and stuff is over the top and just plain too bulky for me. They're almost laptop replacements.
I hear that if you have to go PPC, the Toshiba 740 is the hot ticket, but for now I'm still a Palm guy.
jmx
PS: Whatever you do, don't try the game Bejeweled.