Those who often have to raise sites on Drupal, have a permanent set of modules in the storeroom and those that can be used in one way or another on a lifted resource.
In the absence of this set, you have to remember and download modules for the implementation of one or another functionality on the site.
Since the current version is currently the seventh, we will talk about it.
Administration
The Fubik theme is a very convenient and beautiful admin theme.
Module Comment Access - access control to comments (especially useful for the forum)
Site attendance and analytics
The standard Statistics module can be extended with the Chart API module.
User registration, the creation of various types of nodes is tracked using the Quant module.
Attendance analysis is well implemented using the Visitors module. Problems may arise with it, but their solution is described in the bugtracker of this module.
If you are friends with Google Analitics, then this module in conjunction with this one will definitely come in handy.
Communication
It is wise to keep the Advanced Forum ready on top of the standard Forum module.
Privatemsg module provides private messaging within the site with the possibility of notification by mail
Although the DrupalChat module is in beta testing, it can still do something. In addition, the module is being developed, so it’s better to use it for chatting.
An interesting module to simplify registration, if the form itself, for example, is present only on the main page and not only - LoginToboggan
I recommend Ajax Login / Register to those who want not to bother the user with page overload during registration.
Quick detection of login and email busy during registration - Friendly Register
Simple module for basic spam bots protection - Trick Question
If something important has been published on the site that needs to be read, then with the help of the Login Destination module you can, when logging in, redirect the user to the desired page.
Representations and appearance
Views - I think, needs no introduction. Stuck useful and powerful for themeization of output nodes.
Modules Media and Media Gallary - a convenient combination for creating galleries (photos, videos) on the site. If you add the Embedded Google Docs Viewer module to them, you can create galleries with documents and convenient viewing.
The Mobile Theme module allows you to select a site theme for mobile devices separately from the main one.
Also, a useful module built on the combination of the Form API and the Field API. Drupal - Field collection allows you to present the form as a separate node field.
Development
Module Devel - module for development under Drupal. However, besides the functions for the developer, there are functions for the site administrator (for example, clearing the cache).
jQuery Update - Provides the site with the latest versions of jQuery and jQuery UI.
CTools is an important module that provides various APIs (for example, simplifying the creation of multi-path forms).