embedded networking gateway module or something simpler

My thought is that I need a tiny (1/3cm) spring- like device that can be embedded and will release a thin metal wafer if an incorrect smartcard or biometric is entered. It needs to be low in cost and rugged. Am I in the dinosaur age and there is something more edgy available? I am open to researching in whatever direction you can helpfully point me.

Thanks-

I wish girls had been directed toward engineering in the 50's...... Granny steadily losing ground