I need to take medication before I go to sleep but sometimes forget. My solution is to have an LED start to flash in my bedroom at 2100 hrs and a button to press to stop it until the next day. When I switch off my light to go to sleep I'll notice the flashing LED, take my happy pill and hit the button to reset the controller until 2100 the following night. What would be a suitable microcontroller to do this? I figure it needs an RTC to know when 2100 hrs is but if it's simpler maybe it could also be set by just plugging it in at 2100 hrs and it could then count 24 hour periods from there.