show_and_tell.rb

#!/usr/bin/env ruby

def get_time(format="%H:%M")
  Time.now.strftime("%H:%M")
end

case get_time
when "09:00"
  `say you should finish your breakfast in 10 minutes`
when "11:55"
  `say lunch in 5 minutes`
when "17:40"
  `say show and tell in 5 minutes`
when "17:00"
  `say Beer time` if get_time("%A") == "Friday"
end