Tauno Hanni

This plugin is a developer’s toolkit for collecting form data from your WordPress site. It provides the necessary hooks and utilities for you to manage how data is stored and displayed later.
The best way to get started is to look at example-functions.php and example.php in <code>/plugins/form-data-collector/example</code> folder.
You can see a list of utilities and hooks <a href="https://github.com/taunoha/form-data-collector/wiki/" rel="nofollow ugc">here</a>.
Not compatible with 1.x.x versions 🙁

Form Data Collector

This plugin will help you to collect and store form data.

tmertz

Designed to make it easier to serve signup form on sites for LARP activities, this plugin aims to be very flexible in the way it handles input form fields.
What makes this plugin awesome is:
<ul>
<li>the ability for you to define the form you need to get the data you want.</li>
<li>the fact that it has been designed with the less is more paradigm in mind.</li>
</ul>
Thank you goes out to nkuttler of the IRC channel for his help sorting out my problems with $_POST.

Osmig Signup Plugin

This is a simple and flexible plugin to handle signups with the form fields you define.

Form Data Collector vs Osmig Signup Plugin