My second brain

I bought my Palm Zire 72 over three years ago and I've just recently had to replace the battery. That is the extent of my complaints of this wonderful little machine.
It is expandable to the extent of whatever SD cards you choose to use. I've used them to download excel files from work without any problems. The MP3 player works very well, and the software is easy to use. Simply hotsynch your songs and you're good to go. The graphics are much better than some of the other Palm models I've seen as well.
I used this primarily to keep my contacts in one place and to organize my calendar. I also used it in conjunction with my boss's PDA and synched his calendar and to-do list to mine without any issues. The Palm software is easy to use and understand. It does have Bluetooth capability, but I never had a reason to use it, so I can't say much about that feature.
It's a hardy little PDA that can withstand a lot of use and abuse. I recommend getting (and using) the screen savers so that your screen doesn't wind up cloudy from all of the scratches it may accumulate over time.