Thanks for the link. That's the first time I've seen an implementation. And I've looked at a bunch of devices from different vendors. Unfortunately, this means

Thanks for the link. That's the first time I've seen an implementation. And I've looked at a bunch of devices from different vendors. Unfortunately, this means that i can have my own key if I avoid tablets and laptops, and only build my own hardware. I'll still have to use Canonical or RedHat's (possibly NSA/GCHQ-compromised) keys in order to have portable computing.