APIs and innovation

I had written a while back about Skype's API. I found out recently that someone's developed an answering machine application using the API:

SAM is a simple voice answering machine for Skype® users.

When you are away from your PC and there is no one to answer your incoming Skype calls, SAM will pick up the call, play a greeting message and the "all-time clasic beep" so that the calling party will leave a voice recorded message.

It looks a little rough around the edges right now, but I still think it's a great example of how opening up APIs, done well, can fuel user-driven innovation. Apropos of this, also see the recent Google AdWords API announcement:

Google's free AdWords API service lets developers engineer computer programs that interact directly with the AdWords server. With the applications created, advertisers and third parties can more efficiently - and creatively - manage their large AdWords accounts and campaigns.

From the Google Blog:

The AdWords API beta program is an open invitation to developers to explore new concepts (and then write great software) for managing Google AdWords advertising campaigns. Large advertisers can use it for their complex ad management needs, like tying product margins to optimized keyword bids.Third parties can use the API to build new interfaces to manage their client accounts. Best of all, an API enables the creation of all sorts of unanticipated ideas.