### Clue: Beam serenely, foolishly ignoring unknown computer scientist (3,7-3)
### Answer: TIM BERNERS-LEE 
 ### Explanation: Definition: computer scientist
A charade of TIMBER ('beam') plus NERSLEE, an anagram ('foolishly') of 'serenel[y]' minus the Y ('ignoring unknown'), for the inventor of the World Wide Web.