On my flight to Barcelona, I had a layover at London (see my previous post at Celebrating the New Year in London). Not only was it about 10 hours of layover, I had to change from Heathrow airport to Gatwick. Best of all, we landed at Heathrow at 4:30am, which was the time that Heathrow was actually open (thought most major airports were opened 24/7) and so our flight was hovering for 5 mins since we got there early.
No sweat; at least I got to ride on British Airways business class.