Have you ever wanted to completely isolate your private keys from networks and removable media? Armory nearly accomplishes this, but still requires removable media to move the transaction content back and forth. I've created an Android app called Armory Companion that allows you to broadcast signed transactions on the bitcoin network after signing with your offline Armory instance (or any other bitcoin instance for that matter) using QR code scanning. There are some tiny python scripts that run on the offline computer to facilitate QR code scanning with the webcam and generation of the final signed transaction QR code.
See this video for a demonstration of how it works:
http://www.youtube.com/watch?v=ZlSC3mLjNSgThis post shows that this is something other people want, so I figured I'd share it:
http://bitcoin.stackexchange.com/questions/8101/how-to-sign-a-transaction-using-only-offline-computerThe code is here:
https://github.com/hank/armorycompanion-pythonhttps://github.com/hank/armorycompanionFeel free to fork and modify as you desire. The app will be on Google Play soon.