Enlight (English version exists) is an open source framework, based on Zend and Symphony 2, for creating e-commerce applications easier and faster.

It is built by the experienced e-commerce company Shopware and also powers the base behind their commercial product.

The framework has lots of components that can bring any type of apps to life including: database connection, authentication, form handling, datagrid, navigation, e-mail delivery and more.

Besides the frontend, a base with similar features exist for the backend where both parts can be improved with the help of a plugin system (a bootstrap file is provided for creating new plugins).

Enlight is not a direct competitor to any ready-to-use e-commerce system but a starting point for anyone looking to develop custom ones.

PHP Bug Lost is a free and open source script for debugging and monitoring PHP code.

It is a one-file-script, works by inserting a function inside web pages and displays the information in a console window right over the web page.

The script can present custom logs, SQL queries, variables, Ajax queries and measure loading times + CPU/memory usage.

PHP Bug Lost is not only built to be used in the development environment but it can also be set to auto-send e-mails when any of the monitored data is over or below the expected values.

Almost every website owner tracks the statistics of their websites with the free and powerful Google Analytics.

The service has made a huge step forward with its "live stats" feature which shows the instant activity.

There are very few reasons left to use another solution to track stats where one of them is the lack of "live overall stats" (as Google Analytics still displays the overall stats with a delay) and the other is the need for using an open source system.

For anyone looking to see the overall stats in real-time and needs a simple/lightweight solution (compared to other options like Piwik), ChiliStats is an alternative.

The application is free, open source, built with PHP and uses MySQL for storing the data.

It presents a snapshot of the statistics -supported with charts- in a "OneView" page and sub-pages for viewing top-referrers, visited pages or referring keywords exist. And, a "History" page allows digging the statistics of past months.

ChiliStats also offers a stats counter widget to be integrated inside web pages.

GoCart is an open source e-commerce application which is focused on offering an easy to use/customize solution and not having a huge number of features but only the important ones.

It can have unlimited categories, tiered categories with any depth, unlimited products-product images-options and can display related items.

The built-in shipping methods include a flat or table rate, USPS, FedEx + UPS and has support for Paypal, Authorize.net and "COD (collect on delivery)" payment methods.

Users can have multiple addresses with the help of an address book and use giftcards or coupons with the system.

A plain admin panel empowers the store owner with features like the ability to configure categories, products, export user + sales data, get sales reports, implement promotions and create/edit content within the site with a simple CMS.

AB testing is great for fine-tuning almost anything in web pages (design items, content, etc.) to find out which ones convert the best.

Instabir is a jQuery plugin for quickly implementing AB testing with a few lines of code.

It works by simply applying 2 different designs, content, etc., hiding one of them and defining these HTML elements, plugin displays only one of them randomly and records the activities into a MySQL database.

There is a PHP file provided for handling the requests and recording them to the database.

Instabir also has a paid service which records all the activities itself and can present the results visually.

AMPPS is a software for quickly installing Apache, MySQL, PHP, Perl and Python and creating a web server environment.

What differentiates it from other similar solutions is the built-in Softaculous package which makes 1 click installations of popular web apps possible.

There is a huge list of installable apps (250+) including WordPress, Joomla, Magento, phpBB and much more.

Using the AMPPS panel, the server resources can be configured and all the installations can be managed.

It has versions for Windows + Mac OS X and also installs phpMyAdmin + SQLite manager for controlling databases.

Working with images and resizing or cropping them can sometimes be challenging as there is always a math going on behind: the ratios, resizing with the width or height, x-y values for cropping, etc.

phpThumb is a PHP library that handles all the hard work on creating thumbnails with only few lines of code.

It accepts any source types for images (from the filesystem, URL or database) and all popular image formats.

Images can be rotated, cropped, watermarked, their quality can be defined and there is even a built-in caching to minimize the server load.

phpThumb also has a wide collection of filters including contrast, blur, brightness, applying rounded corners and more.

selfoss is an open source and lightweight web application that can fetch content from any number of sources.

RSS is the content type supported by default, however, with its plugin system, any new source types (log files, e-mails, etc.) can be implemented by adding a single class.

The application has a simple-yet-functional interface which also supports navigating via keyboard.

It is also flexible in means of the database used; you can either go with MySQL, SQLite or MongoDB.

There is a "getting stronger" opinion and movement on web users having their own self-controlled, free and open source clouds where data belongs to the users, can be transferred easily and privacy is not an issue.

ownCloud is supporting this movement with a cool app which works as a:

• file manager/explorer with share option, WebDAV support, the ability to play music files
• calendar
• contacts manager
• and has planned features like image gallery, online text editor, online task manager, encryption, bookmarks, desktop sync client, Android&webOS apps and server-server sync.

It is built with PHP-MySQL (or SQLite) and is definitely a good option for users willing to move their data to the web + manage easily.

For MySQL users, phpMyAdmin -the popular MySQL admin tool-, is probably one of the most-used apps unless you are fan of a desktop MySQL admin tool.

MyWebSQL is an exciting open source alternative to both as it is a web-based MySQL (and SQLite) manager with a desktop-like functionality.

It is built with PHP and, with the help of a completely Ajaxed interface, tasks can be accomplished pretty quickly.

Creating, editing and deleting tables or records are easily done in a grid mode which also makes working with multiple items at the same time possible. Also, shortcuts for any actions exist inside context menus to make browsing faster.

There are other must-have features like import-export, SQL editor (with syntax highlighting), repair tables, search, process manager, etc.

MyWebSQL is a multilanguage app with lots of ready-to-use languages and has a themable interface.

Imho, what is missing the most is the ability to manage multiple server connections with a single login and scheduled tasks (which I hope would exist in the future versions).