[3amOpsGuy]

Would something like Keycard[1] work for locking the screen when you're not nearby?

I wonder if it could be set to lock at boot unless your phone (or BT headphones or whatever) is nearby.

I doubt this can be all that secure since it can be downloaded from the App Store, I'm pretty sure that means it can be force quit (it could not prevent this key combo since its restricted in the sandbox). It may be just enough.

[1] http://www.appuous.com/products/mac/keycard.html