PlayStation, Apple TV, Xbox. The encroachment of technology services into the living room is more or less complete. I can't remember visiting anybody recently who wasn't rocking one of these devices in their home.
Which raises some interesting questions about the balance between security and usability for a device and service for the whole family which is tied to one user's account.
At the moment most of these devices rely upon you either giving any user carte blanche to purchase content with your account or being there to authorise each purchase by entering a password.
That's not really useful in a context where we're more and more expecting these services to replace the broadcast media we've been used to consuming.
There are shortcuts - an Xbox equipped with a Kinect sensor will see and recognise you; and sign you in automatically. Apple is rumoured to be adding Touch ID to the next Apple TV remote control and Sony....
For now separate user accounts and a strict bar purchasing content amount to a reasonable work around. That won't always be true. Fixing this issue should certainly be on technology vendor's radar.