Today a rather non-programming-related blog post :) . You probably encountered already the issue of configuring your Wifi access to your home or work wireless system. Usually they're behind some WPA/WPA2 encryption and the key's are usually quite long and cryptic (at least that's the case for my home network). On an Android phone that means weird long typing work, hoping to not miss/mistype anything.
For this to work, you need to have the latest version of the Barcode Scanner app, which is available for free on the Android market.
The web application generating the QR code can be found here.
(As a sidenote: you can create qr codes by using Google's goo.gl shortener and appending ".qr". You may also want to check out the Google Charts API)