what happens when you turn on a light switch?

A 2009 Tipping Point winner, The Light Switch Project, will be broadcast on Tuesday, 19 April, on BBC Radio 4, at 11 am.  The story follows the actor Toby Jones as he tries to figure out what happens when you flick that switch.

See also: what you are doing when you flick that switch
assessment of latest tipping point commissions
Tipping Point winners announced tonight