Drupal module list: lesser known

Huge list. I'm sure they will help me in the future... if they are not currently used yet!! Always rely on community modules!

AES encryption

encryption / decryption API (readable passwords)

AudioField

adds new field that allows you to upload audio files and automatically displays them in a selected audio player.

Bad Behavior

set of PHP scripts which prevents spambots from accessing your site by analyzing their actual HTTP requests and comparing them to profiles from known spambots.

Better Exposed Filters

replaces the Views' default single- or multi-select boxes with radio buttons or checkboxes, respectively. Description fields and Select All/None links can be added.

Bundle copy

export/import support for: Node types / Taxonomy / User / Field API fields /Field groups

Compact Forms

put labels inside fields and fields on a single line

Custom Contextual Link

add links to the contextual menu items (nodes, views, local actions, ...)

UUID Feature integration

add import / export node content functionnality to Feature module

editablefields

allows fields to be edited on a node's display (e.g. at node/123), not just on the node edit pages. (see also edit module and spark distribution).

env

make Drupal's configuration (settings.php) environment-dependent, so that you can have different sets of configurations in dev, staging and production.

Environment Indicator

adds a coloured strip to the side of the site informing you which environment you're currently in (Development, Staging, Production etc).

Finder

instant AJAX search on faceted items (nodes / users with specific value)

FullCalendar

enhanced calendar based on Adam Shaw's FullCalendar jQuery plugin.

ImageCache Actions

add processing to images: rounded corners, overlay (with text or another image like photoshop layers), canvas manipulation, different effect if landscape, ...

Image Lazyloader

images will only load when it's visible to the browser window (when scrolling).

Language icons

for language switcher block and node links

Menu Admin per Menu

allow only specific roles to manage specific menus.

Menu Firstchild

create a parent menu item without any path (not linked to a page)

MERCI

Manage Equipment Reservations, Checkout and Inventory

Module Filter

add a navigation on the left side and search box on the top for module list page. extremely useful.

Multi-step forms

help to create advanced multistep forms. Field group module can help as well

Entity Connect

expands reference fields by adding a add new content and edit current content button.

OM Maximenu

add text, images, menu blocks, ... to navigation

Override Node Options

allow users to override authored by and / or promoted and /or published and /or revision and /or sticky. Works well with Node and Comments Form Settings. Simplify can be used as well

Panels Extra Layouts

provides a set of fixed (11) and adaptive (2) layouts for Panels. With the adaptative you can build 25 different layouts. simply too easy!

Plup

provides a field widget for image field that allow user to upload multiple images at once.

Protected node

restrict access to a node with a password

Registry Rebuild

can fix Class not found error when moving / deleting modules. Integrated with drush.

Renderable elements

extracts elements from their container to separately access it (in fields display, or Panels)

Remote Aegir Import

provides a UI for fetching sites from remote Aegir servers. A must when you need to move to another server.

Reroute Email

intercepts all emails and reroutes them to a predefined email address. A must on dev / stg environment. Check mailog / mail_logger

Search 404

Perfom a search based on the url whan a 404 occurs

Secure Site

restrict access to the site to authenticate users with a browser-based password (HTTP Auth).

Select (or other)

select/radios/checkboxes element that has an 'other' textfield option

Sheetnode

integrate sheets (Excel, Open Office, Google) to be visible on the page

Smart IP

identify visitor's geographical location (longitude/latitude), country, region, city and postal code based on the IP address of the user.

String Overrides

quick and easy way to replace any text on the site

Tab Tamer

re-ordering, hiding, and deactivation of tabs and subtabs.

ThemeKey

Allows you to conditionally switch theme

Total Control Admin Dashboard

default panel page with useful administration tools

Twitter Pull

super-easy embedding of public twitter data

View unpublished

grant access for specific user roles to view unpublished nodes. A must if you allow people to unpublish content.

View conditional

allows you to define conditionals (if xxx then yyy) with fields in views.

Views content cache

caching for views, until the content in those views changes.

Views Hacks

Views add-ons that provide useful functionalities ("Reset" button to exposed filters, displaying hierarchical taxonomies, ...)

Views Fluid Grid

displays the view as a fluid grid using an HTML list element.

Views Reference Filter

Populate exposed filters + subquery features

Views UI: Edit Basic Settings

Display a simplified interface for your client to just edit the header / footer / number of items

WireDocs

remote file editing tool. it opens the (Word e.a.) file in the browser so you can edit it then close the application. Like Sharepoint or Alfresco.

Wysiwyg API template plugin

allows a user to select a HTML template from a drop-down and insert it into the WYSIWYG text-area.

WYSIWYG Tools Plus

creation of tabbed and accordion drop-down content to be created through the CKEditor interface

The bootstrap override the values you could set to display error ad the reporting level. To be 100% sure everything is printed out when something fails in a blank screen (wsod), make index.php like this:

Properly render a field

Drupal offers a few (sometimes complicated...) solutions to output a field. Lets take an example with a date field.
To display the full rendered field: field_view_field()