Well, apparently Owen's comes with some sort of alarm.
It's a blaring, "Eh, Eh, Eh" sound that actually gets louder as he gets closer via his magnet.
It also has different modes depending on the severity of his desire to magnet himself to me.
There's the one where he's just curious where I am. "mum, mum, mum."
Then the one that means someone has done him wrong, "EH, eh, EH, eh."
And the most desperate, "WEAH! WEAH!"
You get the idea.
Oh, and usually his magnet leads him to one of two places first in his attempt to follow me...
...the office (where the computer is)
...or the bathroom.