Android Desk Phone Tablet I have been using VoIP for my landline for years, with an analog telephone connected to internet via an ATA.
Recently, this Grandstream GXV3175 PoE video phone sparked my interest in upgrading and getting rid of the analog phone and ATA, but now I wish to upgrade to an Android system with camera and market.
It could then also serve as a simple always-on portable PC for quick lookups or web browsing, and basic organiser/games/multimedia…

There already are several ideas for using Android systems as a desktop phone:
  - Android desk phones with Power-over-Ethernet
  - Android desk phone tablet+dock, for landlines with xDSL  

Budget/specs-wise I like the Archos 80 G9 tablet. And ideally, there would be a Telpad-like dock but with PoE, but since that is not available for the moment, I was thinking about just connecting an external handset to the tablet in order to have proper microphone quality. Here I see 2 possibilities:
  1. via an USB port, e.g. Tiptel or Digitus
  2. via an earphone port, e.g. iPego or Moshi Moshi

However, if I read up correctly, none of the above seems to be supported on Android tablets?!
  - Does the OS (3.x/4?) actually support the USB handsets or are there drivers readily available?
  - Are there Android tablets that have a 4-band or 4-pole earphone port with support for an external headset/handset with microphone?  (Above-mentioned iPego or Moshi Moshi handsets are for iPhone/iPad only…)

How can I do this? Any suggestions/alternatives?

PS: sorry, new users can only post a maximum of two hyperlinks :/
For external headsets you would be better looking at the incredible range of bluetooth enabled headsets for mobiles. I doubt that there will be any support for the current desktop usb based ones anytime soon as its not the focus of Android atm. A hardware vendor would have to write the drivers for them, or an opensource effort. 

I was just playing with the new native sip voip on Android 4 and its now deeply integrated. I was using the voip account that my home phone uses so my when someone call my house my mobile also rings and uses the wifi, very cool I wonder if this will pick off.