I had what I thought was an excellent suggestion for PubNub a few years back -- that they support the <cloud> element in RSS 2.0.

When I first wrote it up, SOAP was the big deal in web services. So I called it SOAP Meets RSS.

It would give them a super-simple API, and one that's part of a broadly-supported standard. Nothing ever came of the idea. 

I get emails from them pretty regularly about seminars I could attend to learn how to code to their APIs. Every time I think how great it would be if they used our pre-existing API. Lots of stuff would "just work" and it would be a super easy way for people to get started with their notification service. I still think it's a no-brainer. I don't think I ever wrote a blog post about it, so now I have. ;-)