I bought a china ebook reader; I dismounted it to look for something useful... http://img856.imageshack.us/i/ebookreaderwifi.jpg/
You can see wifi card (top left),and a 4 wires connector, marked as "connettore pannello touch": it's the connector to the touch panel, which makes a standard LCD screen a touch screen.
I wonder if it could be interfaced to Arduino.
And what about the wifi card? As far as I was able to find around, it's just an old RALINK USB WiFi adapter: can it be connected to arduino in some way?
Would 90 euros for these two things be a good deal? There is also a (not visible) microsd slot.