I just got a Zipit Z2. I installed OpenWRT and it is up and running and connected to my router. It should be USB host capable and does have I2C w/o any hardware changes, but I need to build a custom cable. The dock connector is similar to Dell Axim x50 PDA and can still be purchased from digi-key or mouser.

This guy is flashing Arduinos with it: http://hackaday.com/2011/06/13/flash...-with-a-zipit/ (this example was from before USB host was working, so it does include a hardware hack to route the serial interface externally)

Another option would be to use this instead of a Yun (Which also run openWRT) or a WIFI shield. With the extra bonus of the LCD panel, so you know what is going on..

The USB only provides 3.3V when running on battery, so it needs to be plugged in or use a powered hub.

All this for a whopping $19 including shipping - Never used - the box still had the foil on. I have not had this much fun for $20 since I got my first Teensy...

There are still a few available on ebay. An no, I am not the seller or affiliated - I actually just ordered 3 more..:-)

Am I getting excited about nothing or is this pretty cool?