You all need to investigate Armory wallet offline and online desktop version. With the offline version it does not need the block chain just an offline version of Armory installed. Then an online version is installed on a live PC connected to the internet. This is used to initiate the transaction whilst the offline version which stores the private key can sign the transaction. Copy this back to the online PC and broadcast the transaction to the block chain. This can be installed on R PI and we should discuss this further to develop a quick easy offline hardware wallet for mass use. Please discuss as I would like to hear your opinions.