My mum was an Occupational Therapist and the catalogues of equipment she used to use were filled with gadgets and kit and stuff that are now commonplace. A lot of them were developed by council OTs working with biomedical engineers.
The material used to make tempur mattresses was first used as a type of support cushion in small amounts, for example, and the conical jam-jar openers were developed for people with limited dexterity.
The triangular prism shaped pieces of plastic that you slide onto the end of a pencil to stop them rolling off a table originally came from teachers who taught stroke victims.