by-products
Here's a great clip of The Angy Birds story, as told by Rovio CEO Niklas Hed and the game's designer, Jaako Iisalo.
Angry Birds is reasonably unique - yes, it's approaching Thomas proportions but one of the first entertainment phenomena to have began as a mobile application and worked outwards rather than coming at mobile as an extension from a.n.other media eg a film.
Niklas explains how Angry Birds emerged from a side project to design 10 small games specifically for the iPhone platform an see what happened, to experiment and light a few small fires.
The story?
'The game itself doesn't explain the story that much...the pigs are coming they steal the eggs, then they are gone...this leaves space for imagination...this is why people are building their own world around it'
It also plays nicely to the by-products notion.
Angry Birds was developed as an in-house project by the fledgling Rovio in the down-time between client work, iterated and refined over time.
'You have to have passion to make great things, but you must be naive too'
Getting excited and making things. Always a good bet.