At IKEA Hacker, Anneke details how she converted the $30 Bitig clock, which has removable magnets on its clock face, into a system to help her three-year-old track the days of the week he attended pre-school. The clock face was replaced with signs for days of the week, while the magnets were converted into "home" and "kindergarten" signs to stick on the relevant days.
As well as regular activities, uses a birthday magnet to hold up a picture of friends and family when their birthday comes around. As well as helping kids learn their routine, it could be adapted for tech-phobic adults who have trouble sticking to a regular schedule or remembering key dates.
BITIG clock into information board [IKEA Hacker]