BA is currently running two digital billboards in London which feature children reacting in real-time to flights going past overhead.
The campaign, which is by OgilvyOne, is currently on display in Piccadilly Circus and Chiswick. Both billboards are positioned under the flightpath to Heathrow and when a BA flight goes past, a child gets up and points to the plane overhead, and then the specific flight info appears next to them on the board. Clever stuff. The film below shows the Piccadilly Circus billboard in action: