A relative was recently diagnosed with pancreatic cancer. There was a need to be able to alert a caregiver (in another room) day or night when a need arises.
I bought a smoke detector and a remote control switch in the evening (overnight from Amazon) and designed/printed and assembled the box the next day. Push the button and power comes on the box, which causes the smoke detector buzzer to sound.

Print at 10% fill with no supports.

Electrical details are available at: http://www.instructables.com/id/Call-Box/

You can go to http://www.3dhubs.com to find a local printer to produce the box.