Scientific discoveries of our time
The google search "Airspeed Velocity of an Unladen Swallow" returns around 600 results. I used quotes in the query so Google returnes only matches to that exact phrase. If all this rings a bell you will be happy to know we now have an answer... Check out Estimating the Airspeed Velocity of an Unladen Swallow. For those of you who think this makes no sense at all, here's a hint. Via Slashdot.
What do you mean, in LEGO?
While looking up my hint, I stumbled on this... Amazing.