At some point, I had a job where they wouldn't allow us to use any thing other than MySQL to store our data. For the best of me, I could not convince management that the right thing to do was to move to a NoSQL solution like Mongo. At that point, my quest started to find a way to create a NoSQL solution on top of a SQL database.
FireSQL is what came of it. This project started almost 2 years ago. I'm just starting to get around to documenting it now. Please has a look at let me know what you think.
If you are one of those that are not allowed to us anything other than MySQL, this might be the right solution for you if you are interested in a NoSQL solution built on MySQL.