One of the fastest songs Blur ever wrote–and also their most profitable–was "Song 2," the two minute song that appears as track two on their self-titled album from 1997.
The whole thing came together in less than fifteen minutes; some people remember it being more like ten. It was never supposed to be recorded. They were just using it to warm up for whatever they were going to do next.
But when it WAS recorded, it became a single–and it did very well. But where it made all its money was through licensing: TV commercials, movie soundtracks, being playing at sporting events over the PA.
Blur Manager Chris Morrison esitimates that "Song 2" made twenty times as much money from being in ads than it did from sales. The only thing Blur ever turned down was an offer by the US military. They drew the line at using their music to set stealth bombers.