Easy native HTML5 forms for WordPress. Version 1.5 is unmaintained, but works without issue. 2.0 has been rewritten from the ground, and can be found at https://github.com/libreform/libreform
I rebased this to master in order to get Travis STFU. The solution is pretty hacky so I added a comment acknowledging that, and added a note about the addition to the meta box.
Useful to use the ID in subsmission title