PooleApp – A free, hosted data store for your static sites

An example usage of this service is baking comments directly into your static sites via a build tool like Gulp or Grunt.

Explained in more details here: http://hawksworx.com/blog/adding-a-static-comments-system-to...

The website needs a bit of a proof-reading.

http://pooleapp.com/about/#price "All data remains yours. You can always downlaod all of the data from your forms"