I use my Newton 2000 ...

cool to have a device that gets respect for its age and what it can do.
Also, the SE P800 does organizer stuff for me. I don't need a full PDA all the time - so I have 2 Macs at work, a server at home. If I need e.g. to update addressbook data, I bring it on an external hard drive (an old 40 GB Powerbook harddrive in a portable fw case), so the PDAs main point is to write notes when I don't have a pen and paper. Or when not in the mood to carry the hard drive, then plug the files I'll need on another Mac either to one of the 3 iPods, or ssh to my own account of my Mac to get the data I need.
So, today P800 had to do some organizer stuff to plan some meetings, and to add some shopping list stuff, simply because I didn't have a pen and paper..