[JoelBennett]

But how well do cameras work through walls?

Like Bart Simpson said "No one suspects the butterfly." In this case, no one would suspect their router to be watching where they physically are. Imagine a SWAT team being able to detect where people are within a room before they enter the place - all by snooping through a router.

[imron]

And they don't even need to snoop through your router. They could bring their own and just place it outside the door.

[rrobukef]

They also don't need to bring a router, just a special microwave.