Jammer

The Jammer module hides particular elements from edit forms, similar to the Simplify module. This module is mentioned on the revisioning module/s project page on Drupal.org.

Simplify

From the project page: "Simplify allows particular fields to be hidden from the user interface. This helps to de-clutter forms and present a more user-friendly experience to content editors..."

Message

The message stack of module provides the a great way to create a highly customized messaging and notification system

BFG Repo-Cleaner

If you have commits in your git repo that you want removed, you can use git-filter-branch, but that can be pretty slow. Perhaps you accidentally committed and pushed a password, a db dump, email addresses, etc. BFG makes it easy to clean out those files and does it ~ 10-100x faster that git-filter-branch.

Form Builder

This module is a great way to easily create a form and generate the PHP form structure. Used in the Configuration Builder module.

Drupal code a block with an edit form

Sometimes you need to code a block with an edit form. You could just create a block with the UI but that's not going to be exportable with Features and ctools / page manager. This method uses variable_get and variable_set. You may want to create a custom db table to store the data in if you don't want the variables to be loaded into memory on every page load...

jQuery Update

Updates jquery to the latest version that Drupal supports. If you need the latest jQuery for a project, you'll have to add it to your theme manually and should be included using 'noconflict' mode.