I would love to have a small device that i could place discretely anywhere, say my car or my room that would upon entry give a greeting, similar to Xmen "Welcome professor"
But i would like it to have io so you can make it trigger stuff upon your entry and if possible remember when you entered so it knows when you are exiting and can say "goodbye".
I though maybe an ultrasound or Ir unit to detect entry? and one io port that you can add your own trigger for entry and exit.
This could do things like trigger lights in your room, turn on or off any power source when paired with a relay circuit.
And if you felt like going all out, add simple voice recognition to activate the extra io

