I have a Sony Clie (It is pretty cool, comes with the whole nine yards) It even has dual media capabilities (Memory stick and CF)
The camera takes pretty good pictures, it has a wannabe version of photoshop in it so you can play with the pictures you take.
I also have an iPaq which is an awesome PDA as well, its reliable and extremely easy to use (Especially with the Windows Mobile 2003 OS Upgrade)
But of course they both have the Pro's and Con's.
The best thing about the PPC is its integrated ability to synchronize with anything on your windows desktop. Outlook is almost flawless, in a pinch you can work on Word, Excel doc's without loosing the format when you open them at your desktop. The PPC doesn't have a camera

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I recently purchased the Clie because it caught my attention (and it was on sale) I liked the utilities that come with it. It already comes with a wide range of applications, games and neat utilities like the TV remote control. It always works!
As usual, allot of things go into deciding what kind of PDA you're going to get. Usage, price and learning curve are very important factors to keep in mind.
I use them both for different reasons (Plus, with two PDA's my wife doesn't have to keep stealing mine..

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