Take a look at any of the new breed of Windows Mobile 5.0 devices, such as the Imate K-Jam or Qtek 9100 (TMobile MDA Vario, O2 XDA mini S) if you want a keyboard, both have EDGE/GPRS, WiFi and Bluetooth. Alternatively wait a few weeks for the new updated 3G version of the above or the UK launch of the Treo 700w equiv.
If you don't mind a slighty larger device look at the Imate JasJar or Qtek 9000 (T-Mobile MDA PRO, O2 Exec, Orange M5000 and Vodafone VDA IV). This is a 3G/EDGE/GPRS device with WiFi and Bluetooth and a quick enough processor that you could run Skype when in a WiFi hotspot if you use to speak to business contacts.
It's a rapidly evolving area, so there's loads of choice out there. It all depends what your key needs are.
HTH
Michael