@ze Like a pxe boot? I guess so. That would solve the problem of someone trying to mount /boot and stealing your luks key as well as offering the option to backup.

But in addition to whatever solution you use, the closer you can get to The Stateless Laptop the better.

In the airport example, even if you were somehow compelled to open up the OS it wouldn't matter since there would be no data/state kept.

Curently that requires plenty of bash-fu and external storage. Have fun!