I was toying around with FriendFeed and discovered Google's charting engine. Mmm, pie:

The engine can render Google Analytics-esque sparklines too. The simplicity and accessibility of this API is impressive... it's all in the URL.

Now, I'm a bit agitated by this discovery, as years ago at ProClarity Greg & I built very similar to this API for doing sparklines, bullet graphs, and other datawords. I haven't shared it with you yet, and I should have. While it was no complete charting engine, and neither is Google's, our implementation was all of 300 lines of C#... so you could probably build & modify the implementation for your own specific needs pretty easily. Please let me know if you want it, and I'll throw it up on Codeplex.

The major downside of our & Google's architecture is your data is relayed in the GET URL. It's getting replicated in logs. In Google's case, it's sent naked across the Internet (invalid certificate/no HTTPS), and aggregated in Google's data centers. According to the TOS this service cannot be relied on for uptime or continued compatibility. It will break for FriendFeed someday. Of course, free isn't always free! There's definitely some reasons to figure out how to host your own implementation on LAN & with security if you're using this for sensitive data or critical applications, and I should have shared it long ago.