Just checking if you're paying attention. [There's a little bit of bite in his tone, like he said that with a not-very-pleasant smirk.]

And I think learning your computer system from the ground up is a pretty good use of my energy. [This is, after all, an entirely unfamiliar computer architecture. The encryption isn't his best work, but it's proof that he's been doing some serious code crunching in his downtime.]