I know you said you dont want a phone, but I use an xda 2i and that has all of the above functions you require, it sits in a cradle and talks to your pc through it, it also charges in it..... mine is 3 years old and still going strong......... you can get one cheap too
O2 XDA2 on eBay, also, PDAs, Computing (end time 01-Sep-08 21:14:32 BST)
now forget it is phone enabled, and take a step back and see what it can do as a pure pda
Ringnow.com: O2 XDA IIi Specifications